The former Bolton and Newcastle boss was brought in to replace Paul Ince in mid-December with the sole brief of keeping the club in the top flight and, with three matches to go, he has virtually achieved that, with Blackburn six points above the relegation zone.
"Football today means players stay less now than ever before and you have to accept that," he told the Lancashire Telegraph. "As a manager, a big part of your business is doing far too much business that you don't want to do really."
Allardyce's tenure has not been without its problems, however, as one of his first jobs was to keep Manchester City at bay as they tried to lure striker Roque Santa Cruz away in the January transfer window.
The Paraguay international, currently injured, is expected to leave in the summer but it is the departures of a number of others which could leave Allardyce with a lot of work to do in June and July.
Dutchman Andre Ooijer has already stated his desire to return to his homeland, probably with PSV Eindhoven, while veteran midfielder Tugay has already been told he will not have his contract renewed.
Striker Matt Derbyshire has been out on loan at Olympiacos, Aaron Mokoena's future remains unclear while Chile winger Carlos Villanueva and Manchester United defender Danny Simpson are not expected to be offered permanent deals.
On-loan Marseille defender Gael Givet is probably the only player Allardyce is keen on keeping, but he knows not to expect too much from any of his squad.
He added: "We are in a position where we always have to change more players than we really want to and that brings a lot of instability and makes your job so much harder than it should be, because players come and go almost at the drop of the hat.
"When you are sitting in Sir Alex's (Ferguson's) spot or Arsenal's spot or Chelsea or Liverpool, it is so much easier because it is only ever one or two changes. But when you are where we are, it is four or five."