Whistle Blowers - General Question

I’m watching a “whistle blower” testify before Congress. He’s a federal employee. The subject he’s speaking to is irrelevent to my question.

I know there are whistleblower “protections,” but what really happens when he/she returns to his/her office? Are the quietly ostracized? Careers ended? Take early retirement? Do they get a pat on the back for exposing a problem. What motivates them to take a risk?