One of the major contributing factors is no doubt a lack of ground/earth cabling installed. I purchased some cable last week which we call flat twin and earth in the UK which is basically two strands of cable which are inside a plastic cover with a center core of copper which is your ground. Idea being that if the cables get damaged etc. they will go to ground. Because the Ground/earth has no plastic shielding/cover. But not only was I surprised to find that the copper center core was missing it had been replaced with a piece of plastic as a divider. Its not common practice to run the cables in a single cable either most electricians run like the photo above single strands and all the same colour to save money. Funny thing is though the cost of the twin cable is about the same and obviously takes half the time to install because your only running one cable.
Another factor I discovered is the ratings don’t seem to be correct to the size of cable so would advise comparing the mm dimension to European wiring to get your correct current rating. Because under rating, being put into concrete and no fail safe are pretty much a receipe for disaster which is why we make sure its done properly. Not sure if the electrician who was going to wire the house got offended or wasn’t keen to work alongside a foreigner with western standards but either way he became “too busy” to complete the job and we have now had to source another which luckily enough is the same guy who done the internet cafe.
Some of you may wonder why the ground is also so important it also stops you getting electric shocks off computer cases for example as there is a lot of electricity that needs to get grounded due to static etc. Something people learn from experience.