There's a system called 'parachute payments' where clubs are given some of the Premier League TV money for the first two years after they drop out of the Premier league. There are two problems with this system
1) The Premier League is so much richer than the Championship that even the limited parachute payments mean that the clubs that have dropped down are by definition the best resourced clubs in the Championship. Thus the most likely to get promoted back up. You end up with the so called 'yo yo clubs' like West Brom - too rich to stick in the Championship, too poor to stick in the Premier League.
2) The parachute payments last two years, player contracts generally last three or four. Thus if a club gets relegated and actually doesn't get back up to the Premier League within two years, it's effectively stuffed. This has happened to several clubs - Southampton, Charlton and Leeds to a degree - the result is almost always administration or worse. Most of the clubs who were in the Premier League and didn't get promoted back into it in two years are now in the even lower divisions, because the effect of still being in the Championship with no parachute payments and contracts to fulfil is usually devastating.
There are solution to this that have been discussed. The Premier League board recently debated the idea of making parachute payments spread over four years rather than two but this was rejected by the clubs - obviously, if they pay out more in parachute payments, the clubs in the premier league get less. And most of them are on the edge financially, so it would literally be turkeys voting for Christmas.
The second and, to any sane person, more sensible idea is just pay players less. There are utterly average players getting paid far too much money and also too much money being paid to player's agents. There's a practice where, as well as taking 10% (say) of the players earnings, the agent will charge the club usually a multimillion dollar fee to ensure the player signs a new contract. In any other business this would be at best a conflict of interest and at worst illegal but it's standard practice in football - Portsmouth owe several agents a total of about £11m. That's not to players, that's to player's agents. Why are clubs paying player's agents
at all?
The statistic that is most telling is this one : Portmouth's wage bill last season was 107% of it's income. Tell me how anyone who thought that was a good idea could possibly pass a 'fit and proper person' test.