It already happened to me.
My maine Team in season 2 was in a tought league and end in 5th, on season 3 i end 3rd in league and won the cup, so the cup money convered the CL money that i didnt get, since in CL days i only had 1game i played lot of friendlies, Making me win lot of experience for the players and boosters.
After that i won the league in season 4 and 5.

I tanked one of my other teams in season 3 and 5, because of bad results and low money.
The advantage is that you can buy good players at the end of the season, saving tokens, since they stay more time in the same level all your players will be stronger, reducing the need of New players for the next seasons, and whend you sell them the diference of money compensaste the CL loss incame. For exemple You buy a player for 3M you train him for 2 seasons in same level, in next level If you sell him and you can gain 0,5M.
I became 2nd season 4, won season 6, and this season(7) i have the strongest Team in my league, even without Buying any player, i just got one 18 years old fast trainer.