You will never stop learning new tricks while playing Teeworlds, no matter how long you play. At the same time it's easy for new players to just pick it up and have a blast.
Even at relatively low skill levels the game is a lot of fun - think Worms in Realtime! The antics you can get up to while "hooking" yourself around maps is just silly :P.
Even though the game is playable without issues and characters move like they should, they don't register enemies' mouse movements really well. Because of that, it's hard to tell apart who is a spinbotter and who's a legit pro player.