What a 'Tank' is and what League uses as a 'Tank'

The word Tank is used from WWI onwards when a large armored all terrain vehicle was used to transport infantry. Later it was used as an all terrain vehicle with cannons and weapons to be used as an offensive tool.

These tanks were large, immediate threats that devastated buildings and group fortifications, as well as light infantry. They deflected small arms fire and needed immediate attention, however, a well placed anti tank mine, sticky bomb, or rocket could put a tank out of commission, but was still a threat.

This game does not know what a tank is. Riot seems to think that a tank means they last 4 seconds longer than a squishy, no. Tanks need to reliably and surely get to where they want to go, have a few seconds to do something, then be out. The amount of slows and cc's just tacked onto just about everything, they get nowhere, and die in 6 seconds (at the very most).

The best example of a 'Tank' was Olaf, where Ghost + Ult meant that you WERE going to get to where you wanted to go, and were durable enough to do your thing for about 4-5 seconds then get evaporated, this is EXACTLY what a tank needs to be.

In this meta of so much CC and defense being on every item, it seems a little impossible to actually have a true 'Tank' in this game.