I think that in 99.5% of cases you should start trying to monetize from the very beginning, for three primary reasons: 1. You're more likely to piss of custome

I think that in 99.5% of cases you should start trying to monetize from the very beginning, for three primary reasons: 1. You're more likely to piss of customers if you introduce advertisements/donation requests/subscriptions later than if it is there at the beginning. People like to know what they can expect from a site when they first start using it, and they tend to get very comfortable with a given dynamic. I've been very surprised how offended/alienated people can become if you introduce monetization later...people don't seem to understand about hosting costs or time investments. 2. You get the chance to see what is actually going to work for you before you go through too many iterations of your idea. Maybe your initial focus is not able to sustain itself...being able to adjust on the fly and experiment is a key component of internet sites and your monetization strategy is definitely something you can/should experiment with. 3. People with something invested in your site beyond their content contributions (such as donations/subscriptions) are more likely to give you honest feedback about your site. You also tend to get more partner inquiries if there is a visible monetization method (versus 'labors of love'.)