Either he didn't establish penalty takers, or he chose Archer - doesn't matter which really, they both reflect badly on him, he knows that, that's why he's being mega-defensive and angry about it.
Palace got criticised for sacking DeBoer after 4 games a few years back, but it was clearly absolutely the right decision in hindsight. The big question here is: do we think RM will actually improve?
The biggest problem all his teams have, including us last season and this season, is conceding a ton of goals. There is clearly something not right with his approach to defensive transition as his teams get cut apart after losing the ball. He thinks he's Pep, but Pep teams are drilled to death in how to stop teams getting at them when they lose the ball. Sure, they have better players too, but we had players at the top of the league ability range last season and we still conceded a ton of goals.
I hoped something would have clicked over the summer, or the club would've found a coach to deal with this issue, but neither has happened. Nothing in his career to date has indicated he knows how to fix his team's defensive issues, so why are people still hoping there'll be a change?