Saturday's Barclays Premier League clash at Craven Cottage is a timely reminder for any Fulham player with designs on a move that life is not always better away from west London, with Pavel Pogrebnyak returning with relegated Reading.
Fulham have 11 players who are out of contract or at the end of their loan deals this summer and Jol is confident of retaining them, while respecting a professional desire to move on, if they make that choice. "You can use that cliche the grass is always greener here, probably, and not at another place," Jol said.
"There is a lot of evidence of players leaving this club and they had a better time here, maybe 80 or 90 per cent of the players. But that is quite arrogant to say, because other players go on to bigger clubs.
"Was there one player going to a top club or another club and did better than here? I don't think so. But I won't be that arrogant to say he (the player, Jol refused to name names) should have stayed because maybe they could get 100 per cent more (in wages).
"It's about them, they have to make their mind up. The players who are here, like Dimitar (Berbatov), Sascha Riether, even Mladen Petric, they all like it here. And (Mark) Schwarzer. I think they would like to stay."
Despite departures of the likes of Clint Dempsey and Mousa Dembele, Jol believes Fulham's record in retaining players is good.
"We want to keep our best players and we've been quite successful up until now," he said.
"I really thought we could end up with a problem with, for example Brede (Hangeland, the captain).
"I feel up until now we're capable of keeping our best players. It's only about two or three other players and we're working hard on that front to keep them here."