Here's a link to what I consider the most important article I ever read on photography.
A Lesser Photographer Manifesto
In short, he's telling photographers to create limitations with a cheaper camera and it will improve their art. I only agree with that to a certain point. We live in an ever changing world where you can do incredible things with technology. If it doesn't break your budget and you want to try whatever technical gadget, I say go for it. The thing is, you have to realize that it probably isn't going to improve your game that much or help you enjoy photography more.
Sports and wildlife photography are the exceptions to this rule and they're some of the most appreciated photos. If you're trying to get great photos in poor light, you're going to have to spend some money. It's that simple.
Then, there's the matter of glass. Great lenses make a difference. That's just that simple too. You can still get a great photo without them, but not consistently.
The manifesto's biggest lesson though is that you can use constraints instead of complaining about them. Exhausting the possibilities with the gear you have can be a great teacher too.
Every photographer should at least read A Lesser Photographer Manifesto and consider some of the points, especially beginners or those who aren't happy with the results from the gear they have.