Yep, the problem is there are 12 monorail trains of which 10 are generally running at all times often for 18-20 hours per day so there is no time for maintenance beyond just keeping them running and barely enough time for the custodial crew to clean them. Being something that generates no revenue it's hard to get TDO to spend any money on them beyond keeping them running. They are spending money on the new "train control system" which will essentially eliminate the drivers and automate the trains. In theory once the new system is perfected it will become the basis for a new set of trains since the current trains are long past their expected lifespan. Finding the 100's of millions of dollars to replace them will be the big challenge. It's also expected that sections of the beamways may have to replaced in the coming years because it is also reaching the end of its expected life.
A big part of the problem is also the transportation department management all comes from bus backgrounds so they keep investing in buses. It makes sense in a way because buses are not limited to routes served by track, and additional buses can be put into service quickly and easily. The problem is this is a company that provides "magic" and riding a bus is never a magic experience.