Theres no real objective to the game that has a purpose and creates a story that wants u to keep on playing.. its all about click a few things here, collect some resources and check if you can build it. then if you can build that one building and wait for next twelve hours. You also  have to wait for ages for things to be built.  Its get repetitive doing the same thing that never ends and its not fun. Those games ae trying to make you pay for the game  if you can't stand waiting hence microtransansactions. Just look at farmville and you can see why people get bored. Look at frozen, candy crush. all you do is get this amount of this color, get thsi  amount of this fruit and you play few hundreds levels with objectives that changes only by the amount of things you have to get with less moves.  Look at modern combat games (fps). Those games are horrendous to play on touch screen , especially when you can't aim as fast as your controller or mouse . Plus its not responsive enough.  That one is good example of poor controls.  Remember games are meant to capture your interest to keep on playing. the first impression is the most impt  which alot of the mobile games fail to do.

My main complaint with mobile is that it's pretty much the FLASH GAMES of the earlier 00's but now you have to pay for the full experience and/or deal with ads. But unlike FLASH GAMES, there's no keyboard and no mouse.

Small screen (lacks immersion), awkward controls (a rectangle is not a comfortable thing to hold for extended periods of gaming and lack of buttons is huge), I hate having to bend over or look down (hurts my neck or back), and I am only on the go for short periods of time so I would never finish a long game. Why would I play on a 5inch screen while I have a screen 10x that to play on?

Everything i guess.

I won't say the same thing other already did, but i don't see why i should play crap games on smartphone when i can do better/real games on 3ds/vita.