These days, some of the most successful games out there aren't even "out" yet.

That's thanks to the rising trend of paid alphas. While some players show disdain toward developers who sell a game before it's "done," this new funding option has brought us games that may have never seen the light of day, all with the financial -- and creative -- help from an engaged audience.

Steam Early Access isn't the only option for paid alphas in games, but it is certainly the most prominent. We spoke with notable Early Access developers for some insight and tips into their own paid alpha experiences, for developers thinking of going the paid alpha route:

Ben Falcone: Endnight Games - The Forest

Brian Fargo, InXile - Wasteland 2

George Mamakos, Keen Software - Space Engineers

Adam Overton, Uber Entertainment - Planetary Annihilation

Adrian Goya and Bob Holtzman, Squad - Kerbal Space Program

At what point in development did you decide that your game was ready to be released as a paid alpha? Why did you feel that was the appropriate time?

Ben Falcone, Endnight Games: When we ran out of money! Some of the fans were yelling at us to release, our private investors were threatening to sue, and we were down to a few hundred dollars in the bank, so we felt it was time.

Brian Fargo, InXile: Our situation arose out of the fact that we were already going to be sending beta copies out to all of our Kickstarter backers through Steam as per our campaign. Though we had always planned to use Steam for our beta testing, Early Access did not exist when we began development. We then had folks who missed our Kickstarter and wanted to get in on the early playing and all we had to do was flip a switch to broaden it out from our backers. For me the appropriate time was when we could give a good sense of the game, but yet give us plenty of time to modify.

Wasteland 2

George Mamakos, Keen Software: We set the seven-months development deadline right at the beginning of Space Engineer's development - in the same moment as we started prototyping and designing. We didn't know with 100 percent certainty how many features will be ready on the deadline, so we started with the most important ones - mostly those that could demonstrate the capabilities and vision of our game.

Adam Overton, Uber Entertainment: We were playing the game internally and having fun. It wasn't the complete vision for the game by far, and there were plenty of stability issues. Still, it had the main real-time strategy game play, plus it incorporated some of what we expected would make the game unique, such as playing on a spherical planet.

Adrian Goya, Squad: It was part of our plan from the start, before we even started development. The most important mechanics were present in our (admittedly otherwise limited) alpha. You could build rockets and fly them around. Sure, there was no Space in Kerbal Space Program yet, but what we believed to be our core engagements were there.

We started with a completely free demo. This was simply exploratory. We had to make sure the audience was there. The response was absolutely flooring. The download count kept rising and it made it clear we were not alone. Being as development was starting to generate costs and we found ourselves with a very supportive fanbase, we decided to open a Paypal account and accept donations to fuel the production of our game. We’re in Mexico, so handling the donations was met with deeply substantial fees.

The audience kept growing and growing, donations, while slashed, were coming in at good enough rate. The team grew and our needs expanded as well, so we moved into the paid Alpha territory. We opted for a price tag that we considered was fair for the content in the game, and have been growing ever since.

What have you learned about the audience for your paid alpha?

Ben Falcone, Endnight Games: The audience seems to be a lot of people really excited about game development in general. We get a lot of enthusiasm, a lot of comments from people who say they wanted to make a game just like ours. We were pretty nervous going into Early Access but found the audience to be actually really great and supportive.

Brian Fargo, InXile: One of the things that is important in the development of any creative work is to get good honest feedback along the way. Our audience is very passionate about RPGs and their input has made a major impact on the quality of the game. I learn from my audience more than anything. There is a balancing act between telling a narrative story and being open world, and the players were constantly reminding us of their priorities and playing the game in almost any order. We made quite a few changes in expanding the openness. In the beginning, the game had two choices of saving Highpool or Ag Center, but our players rightly pointed out that if that if one area was going to fall then both should, so we wrote another scenario for the player to accomplish their goals despite allowing those two places to be overrun.

Adam Overton, Uber Entertainment: We have a passionate audience with a tremendous capacity to come up with ideas. We also learned that the excitement for real-time strategy games is still alive. Additionally, we priced the alpha at $90 to be comparable to what Kickstarters paid, because we didn't want to undermine the value of those Kickstarters. That taught us that there were still a significant number of people who were interested in backing the game after the fact by purchasing the alpha.

George Mamakos, Keen Software: Having real customers adds some kind of pressure on us, so we need to make sure that weekly updates are on time, with as less bugs as possible and ready to be playtested. Without this, we could end up in a never-ending cycle of ideas, unfinished experiments... the usual game development problems.

Planetary Annihilation

Bob Holtzman, Squad: Our audience, for the most part, is very satisfied with the work we’re doing on the game and believe we’ve been professional in our development of Kerbal Space Program. But it’s important to understand that as your audience grows, so will the variety of opinions you’ll hear in feedback about the game. We realize most players want to know you’re listening and when possible, using their feedback to take action.

Adrian Goya, Squad: We have found a greatly engaged, passionate and loving community that made our project possible, nurturing it from the very beginning. The earliest adopters also take immense pride in being there from the beginning, knowing that the little project they backed blossomed into what it is today.

What have been the benefits of your paid alpha?

Ben Falcone, Endnight Games: The bug reports are really helpful. As a tiny team without a QA department, lots of small things just get missed. Having a large group of people playing each update and emailing us almost instantly with a list of bugs is an amazing resource. The other major benefit is we now have the resources financially to not only complete the game, but to complete it to a standard that would have been impossible relying only on our own savings or private investment.

Brian Fargo, InXile: Having so many people banging on the game for seven months has allowed us to make a far more robust final product, in fact I can't imagine not having a beta program in place at this point. The game is better thanks to those who participated and it's going to make the experience for first time players stronger.

Seeing the feedback gave us a macro viewpoint on the trends of comments and further helped with more specific things like compatilbity issues. For me, comments from early players address issues that would normally come post-ship, moving them up into production where I can do something about it.

George Mamakos, Keen Software: First we know that there's a real community -- people who want to play our game. So instead of working on our game in stealth mode for years and hoping that one day people may enjoy it, we knew for sure that people want it. Later, our community helped us and is still helping shape the game. We implement features that we see are required by the community. (Of course we have our own ideas too.)

Adam Overton, Uber Entertainment: Funding the ongoing development of the game is definitely a huge benefit. You can't make a game like this with the $2.2 million we got from the Kickstarter. Another benefit is having an enthusiastic community of people who play the game constantly and give feedback. While you don't take everything they say at face value, it is useful for identifying areas to consider.

Adrian Goya, Squad: In an industry that is plagued by the problem of uncertainty, the model helped us find if there was an audience for our game. It helped us create a community that was not only engaged with the project, but felt like part of it and was willing to evangelize to everyone who would listen about our potential. Not only that, but we have been showered with feedback and opinions that while not affecting our main roadmap for KSP, have helped us make a plethora of modifications and polish features that we would have otherwise only seen as necessary after release.

What have been the drawbacks and biggest challenges?

Ben Falcone, Endnight Games: The only real drawback has been having to always keep the game somewhat playable. There are times where we want to break everything for a few days to get a new system in, or change the lighting. When the game has to go out to the public 2-3 times a month it means bigger changes are a lot more stressful, and have to be more carefully-timed so as to not break the game drastically for everyone. 

Brian Fargo, InXile: Well the two big issues are that you take a risk by putting out an unfinished game and that it creates a long-term bad impression, and the Steam reviews stay up based on a version of the game that is not relevant (though fortunately Steam tags the Early Access reviews from the final version). The majority liked what they saw and understood the process, but it is a risk. The other drawback is that you are now simultaneously working on servicing an active product with updates while trying to finish the game. Locking the game down for public release every month or so takes time, but again the tradeoff is worth it.

George Mamakos, Keen Software: The main drawback that we had to face was the fact that a big percentage of players and also the majority of the press are still hesitant when it comes to purchasing or covering games which are in Early Access. The biggest challenges were to convince them about the quality of our game and also about the vision and the plan that we had when we first launched it. Also, in terms of development, one of our biggest challenges was to stay focused on our initial plan and to manage the implementation of new features without having too many bugs and without damaging the code.

Adam Overton, Uber Entertainment: One drawback is having an enthusiastic community of people who play the game constantly and give feedback! Hah! Seriously, keeping up with all that is significant work, and there is substantial noise around the signal. Pet features, things people want from other products, "OMG unit X is OP!!!," etc. It can be taxing, but it is worth it. Most days, anyway! We also got some grief around having the alpha so high-priced, but we felt staying true to our Kickstarter backers on that issue was too important.

Adrian Goya, Squad: We had to follow a completely different development process from the standard in gaming. Every little update or patch had to represent a noticeable upgrade from the previous, so much so that it could stand on its own or even as the last one. Add to that the rising standards within the community and the passion of our fans and you have a recipe for potential disaster.

Bob Holtzman, Squad: One of the most difficult aspects is managing expectations with your community. And as KSP grew, it meant we were going to have many different voices and opinions being shared with our team. For the developers, who were just learning about this aspect of the community, it was a challenge to digest all of this information and figure out what was important. We wouldn’t necessarily call it a drawback, but as Early Access programs are still new, it’s important to consistently remind players what our program means and how we intend to live up to our end of the program. 

What are key pieces of advice for releasing a paid alpha game?

Ben Falcone, Endnight Games: Don't Starve had a countdown timer for days on the front screen, and let players know exactly when the next update would come. We thought this was an amazing idea and took this a little further and instead added hours, minutes and seconds to how long until next build would be out. I think it's something the public has responded to really well. Every-time you load the game your reminded as a player that the game is still being worked on, and you know when the new update will be out.

Brian Fargo, InXile: A developer really needs to make sure that what is being released shows the potential of what is to come or that first impression could make a later successful launch impossible. And when you put a game out for early play you better be ready to listen and have the resources to make the changes that no doubt will come in.

George Mamakos, Keen Software: It has to contain the core features. For example in our case it was the physics, volumetric destructions and building tools. If we started with let's say a game where you can pilot ship in space but with none of the mentioned features, people wouldn't get anything special, we would lose their interest. Then there are weekly updates and listening to the community.

Adam Overton, Uber Entertainment: It's really important that your game contain something novel as a reward for being in the alpha. Be prepared to interact with your audience. Make sure you're likely to be able to follow through and deliver your game. People in your alpha are essentially paying for the full game, plus being able to witness the creation process. It's like pre-ordering, only you get something for paying early. So make sure you deliver that value by engaging with your community.

Kerbal Space Program

Adrian Goya, Squad: Commit yourself to quality and make sure you are charging the right price for your game. If you give your project a lower price than the content within it merits, you’ll take funding from the future of the project and compromise it all. Charge too much and you’ll end up alienating any possible support you could have had.

Test. Test and test and then test some more. Then make sure that those tests were properly tested. Most players will only be willing to give you a single shot, and having them turn away from your game because of a bug that you could have found and fixed means that not only will you have kept yourself from adding another supporter, but you have lost everyone that supporter could have talked into giving you a chance. Do not rush anything.

Have a well designed plan from the beginning of your development to 1.0, but make room for feedback from your fans. Keep in mind though, your community will have a lot of good insights and points of view that you had never ever considered, but they must remain your advisors, not your guide. If you try and please everyone and lose touch with your vision, you will end up pleasing no one.

Bob Holtzman, Squad: Be honest with your community and yourself. Your community is going to be the reason your game succeeds. If you can’t be honest with them, they will share that with their friends and the chances of them asking their friends to play with them is diminished.