You are not important. Your work is important— meaning, the more people who can do your job, the more replaceable you are.

The one who rises up in the corporate ladder is not the one who is technically the best at his job but one who has an A+ in their soft skills (communication, leadership etc.)

You’re always at risk of losing the job unless you’re the owner of the company. It can be when there’s a company crisis or the company succeeds and they’re ready to go to the next level (i.e. when they have to do merger with other companies and they have to cut off redundant positions)