Coach Martin having two players transfer is merely the average and the reality of today's Division I college basketball. I don't think we should assume it's a reflection on the coach as much as it is young player's unwillingness to wait their turn on playing time. See the following articles for data on this:
https://herosports.com/college-basketball/transfers-umkc-nevada-ahah
http://www.ncaa.org/about/resources/media-center/news/new-data-shows-transfers-division-i-mens-basketball-remain-steady-over-recent-years