The biggest benefit of bootstrapping is that it keeps your focus on your customers and building a product with value, rather than "your next round". I'm also not sure where you get the "3-6 months" timeframe for bootstrapping, or what that means, since you don't need to wait for anything to get started.

I am trying to put together a beginner friendly guide on startup funding, please let me know other materials/sources that I should be including...