Are you seriously saying you spend 8+ hours a day working for a company and don't have a contract that manages your rights (like salary, PTO, ...) and obligations (work hours, presence, ...)?
Most American workers have an employment agreement with generalized clauses to the effect of "we can terminate you at any time for any reason" and "hours are thusly unless management needs you otherwise" and "duties are so-and-so but also anything else we want you to do."
I've had jobs where I kept the software running so smoothly 80% of my time at work was spent with a broom or a rag cleaning because "downtime" was not a thing.
Federal employment laws, state employment laws, and court precedents substitute for a detailed contract for many employees in the U.S.
This is in fact a big reason that companies like to use so many contractors: it’s way easier to manage the downside risk for a contractor because the employer’s liability is scoped entirely to one written agreement. Whereas their relationship with employees is scoped to the broad set of laws and precedents mentioned in my first paragraph.
European here. What do you mean? Employment contracts are not common or mandatory? Unheard of here. I painted my grandma's house for money and we still wrote a single page contract.
There are employment agreements, but they typically only cover protections for the company - not stealing IP, no competition clause, etc.
Since most states are at will employment, you don’t need a reason to fire someone, just like an employee doesn’t need a reason to quit. Both parties can end employment without cause at any time for any reason. There are some varying exceptions to this, but it’s mostly the case.
Guessing here but I think the implication is that courts in the US are unable/unwilling to enforce workers rights even when laid out in a contract. In a post-union US there is not enough organised support for workers unless they are very rich.
Obviously employees all (maybe almost all) have employment contracts
Many W-2 employees still have a contract. It's quite common for an employment contract to exist for regular salaried employees, and extremely common at companies like Twitter.
We do have work contracts, but for salaried employees they are often :
"You work for us, we pay you (salary amount) and you will do everything we ask you to and thanks to 'right to work' laws we can fire you at anytime for any or no reason"
Mind blown.