"You need to accept that people are going to stop playing your game."
So started GamesBrief's founder Nicholas Lovell's talk on player sessions, which may be short, but if the game is interesting enough to bring users back, users may end up spending more time than they first imagined.
"You've always got time to check Facebook, and Facebook's just a game," he said, pointing to the idea that people hold that they can't spend too long on a game but will happily spend hours on something else.
"Your on-ramp has to be better than Facebook's."
This may seem like an impossible task, but Lovell suggested some game design in popular games that draws players back in.
For example, Hearthstone draws players back with daily missions, which allow players to leave once completeted but will bring them back for another play later on.
He discussed using energy systems, which can be useful for setting session lengths and make choices matter more, although it can be seen as "evil", the systems are usually clunky, and it prevents the biggest players from continuing their lengthy sessions.
Lovell suggests allowing players to "potter around" in games, so once they have finished their main "quest", they can have fun doing other things in the game, but makes play sessions longer.
In order to get users to come back, Lovell recommends not to simply think "I'm going to make this game very fun". Social mechanics, the use of competition, and steady decay of the game world can lure players back into the game.