Rising transfer spending is making the job of manager "increasingly difficult," says former England boss Sam Allardyce.
More than £850m has been spent by Premier League clubs in the transfer window, which ends on 31 August.
Allardyce, 62, resigned as Crystal Palace boss in May, citing the demands of club coaching as a factor.
"The difficulty for managers is the amount of money that is being spent," Allardyce told BBC Sport.
The former Sunderland and Newcastle boss said there is added pressure from fans, social media and newspapers, with the expectation the "huge amount of money spent" will lead to the equivalent improvement in the team.
"The actual increase in the team is probably less than 5% and that's what you're searching for now," added Allardyce.
"You're searching for just a small percentage and having to pay millions and in some cases hundreds of millions for that little difference."
Accountancy firm Deloitte said Premier League sides are on course to surpass the record £1.165bn they spent last summer.
Allardyce, who stepped down as England manager by mutual agreement in September after only one match in charge, said last week he would be open to the prospect of a return to international management.
He previously said he had "no ambitions" to take another job after this five-month stint at Crystal Palace ended.
"I'm glad all the aggravation is elsewhere and not with me," he said.
"I'm not that active at the moment - I can just sit back and say I'm not actively looking for something, but if it comes my way, I'll have a chat about it and have a think about it."
Allardyce was speaking at the start of the Special Olympics National Games Torch Run