There are a lot of thing that happen within the game that players find annoying. I don't mean what specific zombies do or specific zombies themselves. I mean actions that take place that we find odd or downright annoying. One of the most common I've done is to dig up a plant to upgrade it. This usually happens with the Sunflower and the Twin Sunflower. Don't be shy in sharing what you've done. This may help for those who just started playing PVZ so they know what not to do.