When craftsmen or even skaters are tested for their skills, they are often asked to make something standard - in the case of skaters, they have compulsory figures. In a way, it's too bad that the same is not required of hobby and amateur photographers. It is in photography school.
Think about it. Your assignment is to make another Pepper # 30. Sure the world doesn't need one, but think about it. First you need a suitably funky pepper, then some sort of setting for it, you need to light it or find the natural lighting that will give that pepper the roundness and the glow and the gorgeous highlights, and you need to compose the image suitably.
What has happened when I have tried that experiment in years past is a technically competent aesthetically horrible image, looking more like an illustration in a scientific text on breeding than a piece of art.
When you take on an assignment which has a 'gold standard' with which to compare your efforts, it is downright easy to see where you failed. You can then try again and keep doing it till you get quality that is at least similar to the 'master' image you chose to copy.
I think you will find it time well spent.
It's too bad that some of the 'art' photographers featured in Camera Arts didn't do this first, then we'd get to see their avant garde and alternative process images at their best.