The three main points
First, granting an option is tax-free. Second, at exercise, the difference between the strike price and the value counts as wage and is taxed through payroll. Third, since a 2023 change, the tax is deferred by law until the shares become tradable if the shares are still locked at exercise. The tax is then due when the employee can sell the shares. With this rule, employees avoid the dry income problem, where tax is due before any cash comes in. An employee may still choose to be taxed at exercise instead.
What startups do with the choice
Grant options at a fair value you can defend, and document the valuation in a memo. Let employees choose their own timing under the rules. Hold the pool in the STAK, so employees receive certificates directly when they exercise. See the pool structure. After exercise, any increase in value up to the exit counts as the employee's own capital gain.
You set the salary once. The payroll has to be done every month. See what we take over each month on payroll and administration for a Dutch BV.
The founder's side
Founders themselves rarely have options. They hold their shares through personal holdings from the start. For the people who set the strike price, this is the better choice. See the startup holding structure and founder vesting. For a comparison across countries, see the European comparison.