Exceeding the annual VAT threshold usually means that an additional registration of a VAT number (in the country whose delivery threshold has been exceeded) becomes necessary and, of course, advance returns, declarations, etc. are required.
The delivery threshold refers to imports into an EU country (distance selling) within one calendar year.
The delivery threshold in the Netherlands is €100,000. If, for example, a trader registered in Germany sells his goods to the Netherlands and the turnover from the Netherlands exceeds €100,000 within one calendar year, then the delivery threshold has been exceeded and registration and returns in NL become mandatory!