This is "technical debt" left over from the Woodward era and shows how damaging poor decisions can be.
Clubs need to be able to "fail fast". Bad signings are inevitable, but you need to be able to move on from them quickly. This is the reason the oil cheats have such a huge advantage. The narrative is they "never miss" in the market, which is bollocks. The truth is that they signed huge numbers of players year after year after year, with no regard for budgets or profitablity, until eventually they landed on a group of players that worked. They "failed" in the market many times, but moved on instantly.
United have "failed" in the market many times also, but we compound our mistakes by overpaying on transfer fees and on wages and since we're run for-profit, we can't just discard a player a buy another so easily. When we fail, we fail slowly, and that's the real problem. How many times do we end up with a player on the books who is little to no use on the pitch, has no market value, and who is earning huge money?
Problem we have is that Sancho's market value is effectively nothing. Simple folk won't understand that, but his wages make him "worthless", since nobody will pay him what he earns here.
The fact is, the best offer we got for him last season was a loan, and it looks like we're not expecting to be able to sell him this Summer either.
Technically, he's a very good player - but he's a problem, and a problem that EtH is lumbered with and can't do anything about. All because we went waaaaaaay overboard on his true market value RE : annual salary.
The future is to sign more players (volume-wise) for smaller fees and on smaller salaries and (crucially!) to move them on very quickly if they don't work. If we sign Zirkzee and he doesn't hit the ground running this season, take £20m-25m back next season and move on etc....