Why do I receive an invoice without VAT?

VAT is not charged on all invoices, why is that?

Although we usually charge VAT on all invoices there is a possibility for beginning flexworkers to work three shifts without VAT. This is because we may pay a flexworker three shifts without VAT ID, in that case we also do not pay out VAT after that we do need the VAT ID and all invoices will also be paid out with VAT.