Personally, I wanted to have everything in place, money in hand (or most of it), and a plan written down. As I learn more and more, it seems that to get to that point (if ever!!), I'll need loads of time and silly amounts of research to cover every possibility. I may come to regret this down the line but I've had enough of planning and I've decided to say "fk it!!" and step off the cliff. I want to fly and commercial was a way to do it and get paid, but I have to remember that I want to fly more than I want to get paid. In the end of all this, if I end up with an airline job, then it's a big win. If all I end up with is a PPL and an odd flight every now and again, it's still a very good win. I guess it all boils down to what you really, really want in the end.
Another thing I've considered is the saving part --- knowing myself, if I had a good chunk of money saved up, I'm sure to have some odd side project that will take up my time and money, thus leading me further and further away from my goal in both time and resources. By closing my eyes and taking the plunge, I've committed myself to this.... any money saved MUST go to flying or else I'll lose my skills and would have to fly some more to keep up. Any money saved MUST go to more lessons to get better. I wager once I've had a good taste of flight, it'll draw me in more and more and it'll just happen.
Lastly, I have to be in it to win it. I could save up for 5 years and do all my training in one go, but who knows what opportunities I missed on those 5 years? I'd rather start now and be in it and be ready and available for opportunities that arise. Who knows, one of those opportunities just might be a solution to my financial problem!
Not saying you should follow what I'm saying, just putting my thoughts to words here and trying to convince myself that I've not gone bonkers!!