Bad sportscasting gets in the way of the enjoyment of the game. It is a something that detracts or lessens the experience of watching a game. Three categories apply to announcers:
1. Nastiness: allowing anger or negativity to creep into the commentary. Mike Patrick is a great example of this kind of vitriol.
2. Drama Queen: creating pseudo-drama surrounding events that do not merit such attention -- read anything that is not about the game or how the game is played. Insert Bob Costas for this role.
3. Self-promotion: (the large ego effect) allowing the sportscasters promotion of career or vanity to prevail over the actual events of sport. Again insert the lilliputian in everything but ego Bob Costas.