Teemo is one of those champions that take the most skill out of anyone in this game.

Firstly, he's very powerful in the early laning phase due to high damage potential and high tactic. However, he's also very limited in that he'll still have trouble fighting nearly every other opponent in the game, which is why Teemo should be respected, and worshipped for not being a flashy 12-15 year old appeasing champ with True Damage, CC, Dashes & Sustain.

He's not a Darius or a Katarina that will get fed and absolutely stomp with no weaknesses in sight. If Teemo gets fed, he still has to play smart and strategize to win, he'll just have an easier time with his (R) and his (Q), but he can't just press (R) in the middle of the teamfight and 1v5 like half the champs in this game and then get away with his forty dashes, invulnerability, CC and bright flashy lights (Which he doesn't have).

Teemo needs to strategize, no matter how powerful he gets. He needs to place his mushrooms with thought. He needs to choose who he'll blind wisely. Teemo will always have to make decisions based on how strong/weak he is, how strong his team is, and how strong his enemies are to build and itemize properly, not building his one-item spike BOTRK. I'm looking at you Irelia. He cannot just press (Q) and do a ton of damage to an entire team, he is usually restricted to just one player outside of his (R) placements. A Teemo player must think, a Teemo player must be patient, and above all else, a Teemo player must be vigilant.

The real reason everyone hates Teemo? Is because dying to Teemo means you were undeniably and demoralizingly outplayed due to your own incompetence.