This is true. If you're a hot prospect or an assest, a company will find it hard to sack you. If you want to resign on your own, they will do everything possible to retain your services. If you're out of a job, other companies will follow you up quickly.
The plan will be to always improve your soft skills as that is the only way that you have a higher hand when it comes to negotiating your pay rate at the office. When you are very good at what you do, no boss will feel like letting you go.