Games with a strong focus on storytelling are useless, especially those with boring, repetitive gameplay (I think playing such games is pointless for anyone who values their time, but this is another story). Games that require you to solve static riddles are similarly useless because you already know the answers.
But in games that rely on talent and/or improvisation, the situation is different. To play games like this and see how the various components interact with one another,
developers frequently design roguelikes in particular.
I play my games a lot when they are being developed to make sure they are tough and have the correct amount of balance; but, once I believe I have succeeded, I stop playing as much.
I take on the most difficult tasks to make sure I can still do them. Even while improvisation still fascinates me, I much enjoy reading the players' blogs about the techniques they have developed and contrasting them with mine. I occasionally attempt to defeat tasks that other players have created for themselves ("Is it feasible to [...]?" or they get high rankings in the leaderboards). Additionally, I enjoy playing with others since it is different.
On the other hand, because roguelikes are never finished, it may be argued that roguelike creators do not play their own completed games. Years after the "initial" release, they frequently receive substantial modifications.
