Because over regulation costs business a fortune in time and money.
Gas engineers have to go to college every five years and take the same exams over and over again. The cost is massive with all the different modules required, basic safety, flues, cookers, fires, boilers etc. Plus the three or four days off of work.
I have now done it four times and every time it has been exactly the same, what is the point !
I did a five year apprenticeship to start with which covered everything, now I have to keep on doing the same exam every five years. We are not stupid, if there are any updates we need to know we can read it in the Gas Safe Magazine.
There is a huge training con here making a very good living of off the backs of gas engineers.