Good Day ,
1-
if you don't vacuum the ac system , moisture remains ,this means that the ac would never get cold but it would be cool.
2.
If you don't change the used drier, the drier is contaminated and restricts the flow of refrigerant, means blow out of lines, overheating and weird sound coming from the ac.
3.
If you don't change the filter for the evaporator , it smells foul in the car, it causes the car ac to only work when the place is cool (when rain falling or in the night ), it causes the 'radiator' temperature gauge to go up, it causes the ac line to constantly blow out after gas up (because of low suction pressure and high discharge pressure and the "tech" don't have a high side gauge connected,) it causes the evaporator fan to fail prematurely.
4.
it you don't change the slack belt, your Ac blows cool ,except if you rev the car then it would blow cold, you would then burn more gas, and you would cause the compressor bearing to fail prematurely.
5. Most important ,
if you don't wash out ' service' the evaporator and condenser , the system is overworked and cause failure to all components.
NB there are other problems so contact a technician that has a vacuum pump, nitrogen to pressure test, because you can't add refrigerant to a moisture rich system .
If your system needs a top up, then there is a leak so fix it. Find leaks by pressure testing with nitrogen, change the drier , vacuum, and charge with the suitable refrigerant with the matching gauge to proper pressures.
Remember Air conditioning is not an exacting science "meaning no Masters for this course" ,so this discussion is always subjected to one's experience and
troubleshooting skills.
if you want some help in troubleshooting split AC / Dx systems, or how to size a room , or if you have a mixed matched ,or how to service an AC, or how to install a unit, or what size of breaker to use ,or solar power units, or how to put in a circuit board with remote for a window unit, or to use the circuit board with remote to operate "switch on and off" any electrical power appliance or device, or fridge problems , or electrical problems,or feasibility study of ac and fridge, i would try to help you out. Email me, please ask nicely
