'[My] signed 20k contract is [...] nowhere to be found': HR informs employee that his signing bonus is $10K instead of promised $20K

Always document everything! There is a reason why you should always keep an electronic and physical copy of any contract you sign with anyone. If that contract is conveniently violated, you should have all the receipts to back you up and to make sure that you are not being used. Furthermore, no matter how kind they might appear, this story will serve as another friendly reminder that the folks in HR are not your friends. They are there to protect the company's interests, and if that means that your interests are affected in any way, then they will blindly do so.

This thread was posted to Reddit by u/billgarrr, who recently signed a nice $20K signing bonus when he was officially hired by the company. His final contract was exchanged through his work email and he didn't keep a personal copy for his records (you can see where this is likely going). After some time on the job, he inquired about that sign-on bonus. During that time, HR changed its system and suspiciously lost all evidence that there even was a signing bonus of that amount. Instead, they offered $10K. We're certain that the employee, who seems to be fresh out of school, feels particularly foolish right now, so while we don't want to make light of his situation, we do want to use this story to reinforce the importance of documenting every little detail so you can properly stand up for yourself.

For more stories like this, check out this post about an employee who was told to do less on the job.