Why does nobody want to defend the jungle and/or use their trinket early?

I've never quite understood those who hug tower. I... just don't really understand.

My lane partner (when bot lane) doesn't usually throw a ward into the river unless I ask so our leash can go undisturbed at least not without warning first, and top and mid hold onto their trinkets long enough that it would have been off cooldown already if they used it to defend jungle.

People don't need to 1v5 if we're invaded, the whole point of defending jungle and dropping a ward is to see what the opponent wants to do early and prevent a first blood that could have been easily avoided. You want ganks, why do you not help your jungler with little risk to yourself? o.O Unless you alt-tab until 1:30, you shouldn't be ambushed since everyone will reach the edge of the river and be hidden in bushes.

Unless there's a Blitzcrank. Hug tower as much as you like then 'cause nope nope nope nope.