I wish people understood more that animals go through puberty just like people do, and that “teen” animals will have new and often unpleasant behaviors as they grow and try and figure out their place in the world.
Many of the animals I see being rehomed are right at the one to two year old mark, when maturity is still an ongoing process and their behaviors get more intense. Be patient with them! They DO grow out of it!
Aster was a holy terror until he was almost 3 and now he’s the best cat I’ve ever owned. If you can’t deal with these changes, adopt a mature animal instead of getting a puppy or kitten, because it’s more likely than not they will have a turbulent teen phase.