Some people!
You are born knowing absolutely nothing, everything you know at this point has been learned, sometimes through experience, sometimes through being told by someone.
I like this industry a lot, especially the lorries themselves and I also like to learn, so I’ve got quite a good knowledge of things over the years.
But try and share that knowledge with some people and they call you a know it all, when none of us know anything until we learn it, if you learn something and don’t pass it on then it eventually becomes lost forever.
I used to get ■■■■■■ off by this, but now I realise that some people have an inferiority complex and hate to think that someone may know something they don’t, I don’t let their lousy attitudes change how I do things, after all they’re the ones with the problem.
On a similar note to the OP, I was taking crane sections to Canary Wharf, they hadn’t even started the foundations yet and we were unloading about 50’ below the level of the water in the dock, the bit we were in had been sectioned off and the water pumped out.
The crane sections were all chained down and one driver was stood on the ground pulling the chain as if it was a rope, I said you don’t want to do that mate, you should jump up on top and pull one side up and then throw it down on the floor, I got told to F off for my trouble.
Less than a minute later I heard a yelp, then a thud and sure enough there was numb nuts flat on his back in the chalky snotty mud with a huge gash in his swede and a length of chain on top of him 
You can’t fix stupid…
Some (lots of) people think not knowing something makes them look stupid. Doing stupid things makes you look stupid. What’s even more stupid is ignoring advice when you’re in the middle of doing something that will end in your lying on your back in a pile of ■■■ with the red stuff oozing.
Not knowing things is normal, as said in previous posts.