Time is an investor's biggest ally. The further away your goal, the more ups and downs you can ride out along the way.
Short versus long horizons
Money you may need within a few years usually leans on steadier classes, because there is little time to recover from a fall. Money you will not touch for a decade or more can hold more growth assets, which swing more but have time to recover.
Horizon can outweigh appetite
Even if you are comfortable with risk, a short horizon often calls for caution — time matters as much as comfort.