Full range of motion, especially at long muscle lengths, tends to build more muscle than partials. Partials still have uses: overloading a strong angle, working around pain, or matching a sport.
Range is often limited by control rather than by tissue, so a client who cannot squat deep with a bar may squat deep holding a post.
Standardise it. The same depth on every rep, every week, or the numbers in the log are not comparable. A deeper squat at the same weight is a real form of progressive overload.