I have used several different garages over recent years. They have been independent garages with decent sized adverts in yellow pages. (so not railway arches type, but still reasonable charges.)
Each time I get any work done I open the bonnet after just to check things. They tend to do the repair ok and at a reasonable price. But simple things spoils the workmanship.
eg jubilee clips not retightened, say there is 4 or 5 bolts/screws securing something one is missing and or others not tightened up or just finger tight, air hoses not reconnected, brake fluid cap not screwed on properly, evidence of cross threading wheel nut and stripping the thread of stud and nut, air filter cover not secured properly, evidence of screw slots gouged through using incorrect screwdriver
Am I being picky? Whats wrong in doing a proper job and finishing it off? The thing is most customers wont bother to check these things so the faults will go unnoticed. Its not very assuring is it, makes you wonder about the workmanship they have done where you can't see if all the right bits have been reassembled correctly.