1.duplicate moves. Why adding fury swipes and double slap when there is fury attack? 2. Swagger Why does swagger and flatter raises the foe's stats? Dous it make them "hurt themselves in their confusion" with more power? 3. Adding detect when you have protect? 4. Spores WOW a status effect move with 100 acc. No fair!
No. 1: For Variety.
No.2: Yes, yes it does.
No.3: Variety
No.4: C'mon, why wouldn't you want a 100 acc sleep inducing move? At least only a few Pokemon can learn it. Also, it doesn't effect Grass Types.
Hope I helped!