New manager gives 2 weeks notice after 3 weeks only wtf

What is really going on with Walmart’s managers. Recently our store had a management shuffle and we got a brand new manager from the cottage program. And after working for a week gives 2 weeks notice. Why? It doesn’t make sense. Walmart can’t keep associates at all for any length of time and now someone brand new can’t cope with the drama and is going to work at a fast food place? Anyone else had this happen at their store?