I've been meaning to write this article for some time and I'm never happy with how it flows. I think it's time I just poured it out and maybe do some adjustments later.
I've seen a few people throw around that if you want a successful game (especially if it's online or for mobile) it should be Free to Play (or Freemium if you want). I think this is inherently true, but most people I've asked don't seem to understand what's going on to make this business model so prevalent for those two cases.
Lets define the success of a game. For most this could be some sort of formula that could relate profit with (for those of us that actually care) some amount of critical praise, player count and the desired impact on the target audience.
All of these goals more or less depend on making people want to play your game. So what's the easiest way to get people to play you game? Just make it free, now all you have to do is convince people to try it rather than the much harder process of getting them to actually put money into something. But wait, you say. I'm no longer making any money from people trying out my product. How am I supposed to make money out of it? There's thing thing called monetization and it's an entire discipline which could be (very horribly) summed up as finding a solution to the problem of having lots of players yet no money coming in.
For most companies this has an inherent tendency to become a really shady practice rather easily. You're luring people in with a premise (free game) and trying to make the game fun so they keep playing, yet not so fun so they actually feel comfortable not purchasing anything. So you're compromising the most important part of your game (the fun part) because you followed the F2P model. I'm not even going into the balance issues you'll have if your game is competitive. Soon you'll be designing your game in a way that will lure players into associating microtransactions with dopamine drips: the waiting games with instant gratification if you pay, the powerup slot machines that get you another roll for a few extra cents, the instant energy refill that lets you play for 20 more minutes today.
Note that I'm lumping convenience purchases like Path of Exile's extra slots as a compromise due to the fact that you will also have to consider convenience as a factor that affects the gameplay. Lumping content behind paywalls also falls into this category. The only alternative to this (that I'm aware of) is to sell purely aesthetics items.
In short, picking a F2P model for your game should be a carefully considered decision. Its main advantage is that it will net you a ton of players (very useful if you're going for a multiplayer title where player count is extremely important) but then you will have to shift your gameplay efforts into making sure some percentage of your player base is spending money.
And this is the part that scares me. You're shifting your design efforts to extracting as much money as possible from your fans. Usually some extremely low percentage of players that spend thousands of dollars on things like hats and slightly faster movement speeds. I could never get behind this practice as it feels intellectually dishonest and the best results seem to be appealing to basic human emotions like gambling and immediate gratification. You're making your product successful not by making a good game that people will purchase, but by luring as many people as possible into downloading it and then convincing some small percentage of players to spend as much money as possible.
Can you do F2P in a way that doesn't make me want to take several showers? Kind of (my moral compass is extremely sensitive). Both Path of Exile and Warframe seem to have found a balance where the F2P model helps keep player counts high, and the benefits for paying are designed for the most dedicated fans in such a way that it doesn't give them competitive advantages or make the game simply more enjoyable for them (game design is hard to quantify).