The brilliant author of this game changing key value store is also listed on his linked in profile as a frontend developer and has this brilliant little nugget to share in his latest post: "500 is an internal server error. It is very critical. It means something has exploded. If the client has encountered 500; "We are sorry to encounter this error. Please excuse us, we are interested."
But we see that; There are developers who use 500 even when giving validation messages.
You cannot take refuge in excuses such as time was limited or the budget was low. Typing 400 instead of 500 is not a very difficult thing!
Anyone who doesn't know where to use which status code is a teapot."