Being forced to play according to the game's schedule instead of yours.
"Events, team events, and limited time quests start at certain times and are only available for a short time. Start times keep changing also. King of the Ring requires nearly hourly check ins to play in more competitive groups."
"Ranking events end at 10pm, players who want to rank competitively need to be online close to then. Red envelopes are doled out at specific times. Matron Rong is only available 8pm-9pm. Curators for crops are only available for 8hours, after which there is no curator. Ranking events are held for about 4 days only. Server reset happens at 12am, before which you can't do certain things and certain resources aren't yet available."
"Timed events, shield expirations, tight economy (small storages for wood/stone etc.), ..."
"Collecting batteries (used for base upgrades) is only possible during certain hours."
"Some time limits on purchasing things from the player market, although they aren't inconvenient for most players, they're just for economic balance."
"Bunny derbies require you to be playing the game during certain times of the day for additional rewards."
"You are forced to open the game at various times of the day to claim energy that expires after 2 hours."