1M to 5M vs 5M to 10M

Assuming 10k in monthly contributions, 8% growth:

1M to 5M is cut down by 10 years by said contributions.

5M to 10M is cut down by ~ 1 year by said contributions.

Thus:

After 5M, the compounding takes over in a massive way, and you might as well spend that 10k you were contributing on lifestyle or entrepreneurship.