Some of the articles' suggestions were good ones. And yes, you should always have some ideas for how to monetize your business. However, one key problem is that if you try to implement a monetization strategy before you build a user base and really understand who shows up at your site, your monetization could be completely wrong.
Consider the following possibilities: your user base turns out to be very broad-based and large, your user base turns out to be smaller, but a significant percentage of them is from a particular demographic or vertical, or your product turns out to be most interesting to other businesses or other websites that want to integrate what you built into their own businesses. Each of these scenarios implies a different approach to monetization.
Given the way your understanding of a market can change as you actually meet the real people who use your site, a change in targeted user base can happen to a lot of different businesses. And if you spend too much time up front working on revenue, you may end up throwing all that work away when you confront the actual opportunities that present themselves.
For some businesses, you may have a precise understanding of who your customers are going to be in advance, and then that turns out to be exactly who they are. If that works out for you, cool. But my guess is that that's not the most common scenario, especially for a website.