There is a theory called "crab mentality" or "Сrab bucket theory". It says that crabs are so stupid animals that alone they could easily get out of the bucket, but when one of them tries to get out of the bucket, his relatives cling to it and drag it back.
Thus, the term "crab mentality" is used to describe selfish, short-sighted thinking, which is set to "If I can not, then you will not be able to."
For example: When a person tries to quit drinking alcohol, and his friends say "it still will not work" and call for another party - a "bucket of crabs". When you get a second education, and friends are loudly surprised, why do you need it - a "bucket of crabs." When you are striving for anything, and you are told that you will not succeed. This is an intolerance towards a more successful member of society.
It's human nature, and nothing to do with it, except one thing - to be stronger than a bucket and to climb forward, even when you are pulled back by a hundred people.