"One of the lads, Danny Rose, was at Tottenham and Daniel Levy is so famously known for being tight and being an absolute businessman, brutal, ruthless businessman," Foster told The Fozcast.
"Apparently, their bonus schedule, their bonus payments were almost impossible to achieve, almost impossible. To actually get paid a bonus, you would only get it for beating one of the big boys, one of the top six teams. So you're talking a Manchester City, Manchester United, Chelsea, Liverpool.
"Apparently, I swear on my life, this is what he said to me, you've got to beat them by two clear goals as well. [1-0] it's not enough mate, you ain't getting that bonus. Winning games, they expect you to win games as Tottenham manager, at Tottenham apparently.
"To get the bonus you have to obliterate your opponent. You have to beat Man City 2-0, 3-0 to get that bonus payment which is bonkers. I was saying 'Rosey, there's no chance, that's impossible'. He was just saying 'I know Fozzy, I know'.
"He said there was one time they were winning 2-0 and in the last minute they conceded a goal and everyone was looking at each other thinking 'OK come on lads we've missed out on the bonus', and they've still won the big game."