Based on your financial expertise, provide your response or viewpoint on the given financial question or topic. The response format is open.

Why do Americans have to file taxes, even if their only source of income is from a regular job?
Companies in the US will take care of paying a portion of your required income tax on your behalf based on some paperwork you fill out when starting work.  However, it is up to you as an individual to submit an income tax return.  This is used to ensure that you did not end up under or overpaying based on what your company did on your behalf and any other circumstances that may impact your actual tax owed. In my experience, the process is similar in Europe.  I think anyone who has a family, a house or investments in Europe would need to file an income tax return as that is when things start to get complex.