Look at our three most successful managers - Arthur Rowe, Bill Nic and Keith Burkinshaw.100% this... And the stats are there to prove it:
Ferguson, Wenger, Mourinho... Nothing special as players, but fantastic managers....
...and in the opposite corner:
Hoddle, Ardiles, Souness, Lampard, Roy Keane!!!
Yes, there are exceptions, but great players don't automatically make great managers, if anything, they have TOO MUCH expectation to live up to!!
Sam Allardyce is about the same level Manager as he was a Player.... He pretty much stayed consistent throughout!
None of them what you would call "world class" as players. The first two solid enough team players with a single England cap each, the latter a Third and Fourth Division clogger at Workington and Scunthorpe