On my workbench I have a plastic dial vernier. It's an invaluable tool for matching drill bits in my miscellaneous box of leftovers with piece of wire or plastic rod. So useful a tool that it doesn't have a place to be put away as I'll only get it out again.
It's also handy for checking measurements on models and other stuff I might be writing about, so sometimes it migrates to the computer. This is a nuisance and I then don't have it to hand at the bench when I'm making stuff.
So, at the last show I attended, I bought another plastic dial vernier. It wasn't as good quality, but it was cheap. Less than a fiver as I recall. (In case you wonder why I don't by an electronic version, I did. The battery always seems to be flat when I want to use it) whereas the original was £15 back in the days when £15 would get you a tram ride to Blackpool and back with fish & chips on the front etc.
There is a reason this thing was cheap. It's rubbish.
The gears driving the pointer are waaaayyy out. Look at the photo, 3.5mm out in 25mm? Imagine what it says at the end of the slider!
So, useless. I don't care how cheap this thing it, it's NOT a bargain. This is the difference between something not costing a lot of money and something being cheap. My original was cheap because it's given years of service. This cost a lot less but is expensive 'cos it's hopeless. Lesson learned, I should have paid attention when handing over money. Please learn from my mistake.