I'm a Robbo fan and don't think he should be sacked but I do think you bring up a good point here. Robbo came on board in 2013 and walked into a team featuring a team of stars or future stars, the NSW Origin halfback, the future Aussie Captain (Cordner), a club legend in Minichello and then the club also signed Jennings, Maloney, Luke O'Donnell and Sonny Bill F'n Williams in his prime.
Then all those great players went away, he had a bad season and the Roosters signed Tedesco, Cronk and Keary which saw him have more success.
Now they've tried to do that again with the signing of Brandon Smith I guess and who knows if it'll work but as a coach Robbo has always been surrounded by superstars, he's clearly a good coach but would he have had the same success over his career if he'd been coaching say...the Bulldogs over the past decade?