Saying "you're not very good at this, are you" while at the same time pulling it out of your arse doesn't make it any less of a pile sh1t than it is.
MOT centres are often not garages.
You are not at any point required to have the work done at that MOT centre.
See, I can use bold and a larger font too, difference being I'm not talking out of my arse while offering 'advice'.
You may be comfortable driving a 100k+ genuine motorway milage advisory riddled bag of tat but don't offer that same nonsense as advice to anyone else.