[fundamental]

Echoing the sentiment of other posters, monetization doesn't make much sense for many projects (beyond accepting tips) as it's more work to do without much $ in return. For success you'd need to invest time into marketing, revamping the website(s), changing how you present deliverables to (paying) users, setup payment processing, come up with a set of plans for various funding levels, etc.

This may rarely work out, otherwise it's a lot of work for below minimum wage. I tried to see if there was enough out there for one project I've been working on for years ( http://zynaddsubfx.sf.net ) and my attempt (like several others in related communities) was a flop. It was interesting from an experience side of things, but in the end the project was too niche to support itself (like I'd imagine most open-source work is).