Explicit forecast period

The years for which cash flows are modelled individually, before the terminal value takes over.

Five years is the market convention, and it's often too short. The right length is however long it takes the business to reach a steady state, meaning stable margins, stable reinvestment, and returns converging toward the cost of capital. A young company earning 40% on capital won't be there in five years. Cut the forecast short and you force the terminal assumption to carry a competitive position that hasn't faded yet.

A longer horizon doesn't make the individual years any more precise. It moves the point where you have to assume normality to a place where normality is plausible.

Forecast until the business is boring, then stop.