She is not counting on a perfect market. She is protecting the one advantage no one can recreate later: time.

At a hypothetical 8% annual return, €500 each month for twenty years reaches €294,510. Continue the same habit for twenty-five years and it reaches €475,513.

The five extra years add €30,000 of cash contributions. Yet the illustrated ending difference is €181,003 because the longer path keeps compounding a balance that has already been built.

That does not make 8% a promise. It makes time a valuable resource: one that needs liquidity, realistic saving and an allocation you can live with when markets stop being smooth.