A pitcher's job is to either protect a lead, keep a team in a game, or simply to keep the opposing team from scoring any runs. While it may be a simple job, there are players that either struggle with this, or play around with it.
An example of the latter is Bob Wickman. Fans of teams that he closed for know what I'm talking about. He always got the save in the end, but he always seemed to allow a couple batters on base in the process or allow a run if up by two, annoying fans and making it feel like he could blow the save at any moment.
Here is a player from each team who drives fans insane, whether it's a very inconsistent pitcher, one with ridiculous antics, or simply a new version of Wickman.