Two of those were due to injuries, which happen. And arguably Myers also was impacted significantly by injuries.
Ryder we got 117 games plus a first and second round picks for. Anyone criticising his selection has rocks in their head. Criticism of Bradley should have a look at the alternatives. It was an incredibly poor draft. And Melksham has played over 150 games already - that does not count as a failure.
I think you have an over-estimated view of how successful first round picks are. And how much luck plays a part.