This is mostly because it was beaten into them that this is a poor mans business and should be done with absolute base minimum effort, tooling and investment. Most customers are to blame too as educated people who have delved into this business or even doing as hobby DIY are seen as "failures". - Ive met people in my time in Pakistan who used to say that opening the bonnet of their car is below their status, only drivers or mechanics do that dirty job.
Its a classist society, and a rotten one at that.