Build something worth maintaining.

Maintenance is the honest test of whether something was worth making. Plenty of things are exciting to build and nobody wants to keep them alive, which is a verdict delivered slowly. Something worth maintaining has enough real value that people will pay the unglamorous cost of keeping it running.

Before starting something new, ask honestly whether you or anyone else will still care about it in two years. If not, either shrink the ambition or pick something else. Building things nobody maintains is an expensive way to stay busy.