If that is the case (and might be the case, that is programmed to occur), then this is bad. It is wrong to 'force' users to spend, even if their team is good enough or the manager did his job as a manager..
On the football side, a team has to make recruitment or changes when required. Not doing recruitment may penalise the team when facing certain situations and will likely to penalise the team much later when the decent-performing years of current players in team are over or when some of the players retirement time has come.
In my opinion, some undesirable things happen in this game because of poor simulation and some things happen in the game in attempt to boost the income of the company. So there are two main things - poor simulation and business. In some cases, both are the cause or are linked.