H1B, L1 etc visa schemes make you indentured to the system. The longer you stay and invest in your home and social life (which as a human you have to, otherwise you become a mindless drone), the more you are indentured to the system. Indenture is built into the visa contract – you cannot quit your current employer and stay unemployed even for a short period of time – even though you did contribute social security every single month, even though you paid all taxes every single month – you get no benefits.
So, you are in constant fear of losing your job and having to throw away your entire investment here. This means you will be pliable in many ways you would otherwise not be. You can be denied promotions, you can be given shitty/grunt work, you can be given borderline unethical work, you can be asked to fire other people in unsympathetic ways, you can be asked to work weekends and nights without any overtime pay, you can be asked to travel very long distances for work in economy class and so on and you shall not complain.
You can only suffer silently until you get another job. Btw, you cannot get any random job you like. You have to get a job where the employer is willing to go through the rigmarole of visa process - which narrows the field significantly.