Why keep releasing contracted players?
Payoffs usually equate to ( minimum) 50% of outstanding contract, and that's if players agree ( otherwise 100%)
Add to that the (albeit lower) wage of new signings, and there is not much of a saving on the balance sheet.
Good to get rid of disruptive/ crap/ useless players, but essentially if you give out 12 month contracts, then you are stuck with them.
Better to let them try harder towards the end of the season, to try to earn contracts elsewhere, whilst the manager is targetting new players for next seasons challenge