I accept that things are different in Thailand but there is no way I'll ever accept no earth cable or any other sub standard work. Nor will I accept what I've just had to ❇❇❇❇❇❇❇ my builders about today. I bought a complete set of lintels for each window and door opening before I left. Yesterday's photos showed a 1.8 meter opening with no lintel in place - we'd had this discussion several times and their latest trick is to cover their sins with render in the hope I won't notice. As soon as the doors and windows are in, I'm calling a halt to the job. It will have to wait until my next trip - I'm not frying my brain anymore. I tell them how I want something doing, they agree and then go away and do it differently.
There may well be some reliable, professional Thai tradesmen around but I've yet to come across any.
My car wanted a new lower ball joint last year, firstly told they are not available, have to go to Chevrolet and buy a complete suspension arm because the joint is rivetted in. I bought a joint in the UK and next trip I took it to a local garage to get it fitted as I have few tools in Thailand. I ended up showing them how to remove the rivetts and replace them with the bolts supplied - this was a fair sized, main road garage.
I think very few people are actually trained in their particular job, or if they are the training isn't up to much. Same old same old.......lack of education.