There are 3 main types on repair work/maintenance.
The first type is NECESSARY -needed for your car to safely perform
The second type is PREVENTATIVE -work that is not urgent but is likely to need attention at a future date
The third type is RECOMMENDED -this is work that is maintenance that could improve how your car is operating.
On every car that is brought into ESP we do a vehicle courtesy checklist. We have had it color coded to Red, Yellow and Green and you guessed it, Red is NCESSARY, Yellow is PREVENTATIVE and RECOMMENED.
And if it is in the Green -look good.