Say I own a US LLC or a SWISS AG as discussed lately a few times here. Both countries have applied withholding tax, say they want to hold 30% will I have to pay 30% of my turnover (which I don't may have in my bank account) to the tax authorities even if I don't have to pay tax because I did not made profits?
If those are paid to Swiss residents are generally refunded while if those are paid to a foreign company there are double tax treaties that regulate how much taxes Swiss company has to withhold.
For example if Swiss AG has to pay dividends to a company in a country that has a double tax treaty with Switzerland the withholding tax could be reduced to zero.