When giving an untamed rabbits a carrot it gives off heart particles and runs away. This causes the player to think that they tamed the rabbit when in fact it is still untamed.

To tame a rabbit you have to stand still and wait for the rabbit to come close, then you give it a carrot and one of two things SHOULD happen: They give off small black particles meaning you need to give it more carrots or they give off heart particles meaning they are tamed. Instead what happens is it starts emitting heart particles along with the other particles making it difficult to see if it is tamed or needs more carrots and if you ignore the first step of taming a rabbit and give it a carrot then it will emit hearts and run away instead of not taking the carrot and running away like ocelots do.

The first picture shows what happens when you go up to a rabbit and give it a carrot without first luring it to you. The second shows the rabbit running away because it is untamed. The third picture shows a rabbit lured to the player by standing still and holding a a carrot. The fourth picture shows the black particles just before it starts emitting hearts as if it's in love mode. The fifth picture shows the rabbit being tamed and emitting a cloud of hearts.