How are you supposed to clear guarded wards, or plant in guarded areas?
We've all had that moment: You go into jungle to place down wards, and someone's already in that brush waiting to ambush you, with no way for you to know that since you didn't have vision to begin with. You end up dying because you can't even attempt to get some vision control. Awesome.
Or that moment where you are trying to clear our some wards with a sweeper, but your enemy is vehemently protecting them even if they won't last much longer.
It kinda makes vision control seem pointless if you fall behind, and that even attempting to try and get some vision is a death sentence. A shame Riot doesn't believe in comeback mechanics for vision.