When do you need better gear?
There are a few situations where better equipment can be helpful. I’ll give you a few examples and some tips to overcome the difficulties.
1. Shooting in low light conditions
Having expensive equipment can help you here, you can have a higher ISO without a lot of digital noise. With my entry-level camera, I can raise the ISO to 400 and it already looks really noisy. With a full frame camera or even an expensive DX sensor you can raise the ISO to 1600, or 3200 and your image is still going to look fine.
2. Sports photography
This is another hard thing to do with an amateur camera, you can still achieve great things. Your autofocus is going to play some tricks on you, so you have to work on your timing. Knowing where and when to press the trigger will help your autofocus a lot. Another thing you can do is to learn the panning technique.
So in summary, equipment is just a tool. It doesn’t help you to shape your vision and buying the latest gear as a beginner is not the best choice you can make. When you find that you have difficulty expressing your vision with your current equipment, then you can start thinking about upgrading.