Mandi's answer is correct.
Show me other countries where expats outnumber locals and I will tell you WHY
100 % true Stranger!
OOOps... some people are very sensitive about "FREE WILL" .... sorry...
the purpose is to keep people under the feet of one sponsor , and to avoid they are getting a good future ahead . you either live like a slave or quit .
The purpose is to protect employers from the expense of interviewing and bringing an employee to Qatar and then having that employee jump to another job leaving the employer high and dry.