I'm not sure what exactly made him qualified to begin with. I remember opening day last year when he didn't know how to use to bullpen phone or something. I get they were trying to hit a grand slam by trying to pick out some kind of genius that was totally off the radar, but he was in way over his head and should not have lasted past even one season. Pitching coach was already axed (was a likewise terrible hire), otherwise the Phillies intend to keep all of their other coaches - who had very little big league experience at any rate, which was a big criticism, so they must feel pleased with how they performed. It wasn't all-bad for the Phillies, their pitching was a disaster, made no attempts to improve it last summer, and the guy they let go went to the Braves and had the season that they had.
They are in the same position the Flyers were last year where the Phillies obviously have to make a move that lets their fanbase know that they're getting serious, and bring in someone who has experience and isn't going to let guys roll over. Andy McPhail made comments that they didn't really want to put any chips to the middle to get into the wild card just to get worked over by the Dodgers. Welp, about that...
Showalter is probably the guy going back to McPhail's time with the Orioles.