There's No Place Like Hoenn - S6-E3
Continuity mistake: When Ash says, "Oh, sure," the top left part of the wall behind him goes from being red slats to being a cream wall. Also, the right part of the wall goes from having no slats after Ash's bag to having some. Additionally, Ash's marks go from being absent to being present. (00:06:08)
There's No Place Like Hoenn - S6-E3
Continuity mistake: When May looks at her bicycle when it is charred in her flashback, the emblem on her hat to the right of the knot on her bandanna is red with a white lining, but in the next shot, that part is white with a red lining. (00:06:41)
There's No Place Like Hoenn - S6-E3
Continuity mistake: In the shot before Ash says that he is hurrying to get to his match, the landscape changes between shots. (00:00:23)
Answer: He is a good guy but just found himself in a bad situation when he worked for Lysander. He didn't want him to harm Ash and his Pokémon when he was trying to get the special bond between Ash and his Greninja to work. He does leave Lysander and go back to being a good person.