Why would you spend £30M to replace one bunch of squad players with another set of squad players? Why not get players in who are better than you have, then the previous first teamers become the squad players?
Of the players we brought in over the summer only 4 have usurped others to be genuine first team players (Yoshida, Clyne, Boruc, Ramirez). That cost us around £20M. We've spent around another £15M on squad players in Rodriguez, Mayuka, S.Davis, Gazzaniga and Forren. That's a huge amount to pay for an improved subs bench.