Investing with your discretionary income allows you to pile up more bitcoin for yourself overtime and hodli till your desired time.
Suppose we can invest the extra income we earn from overtime in Bitcoin assets for the future, instead of just enjoying it for the immediate pleasure. In that case, it will turn into significant savings for us later. We will get good results over time if we invest a little bit regularly. Enjoyment is possible, but building future security is much more critical.