Unfortunately, many people believe lifting lighter weight at higher reps will give them more defined muscles. Which is ridiculous. First, you can’t make a muscle more defined - it’s muscle, ok? Muscles don’t ever get undefined. Smaller? Yes. Bigger? Yes. Defined or undefined? Never.
The reason muscles aren’t defined is because there is a layer of fat covering the muscles. Got that? Defined muscles are the result of burning fat off your body.
The purpose of lifting weights is to make muscles stronger / bigger. Weight training has nothing to do with making muscles defined.
If you want defined muscles, burn the fat off your body… typically achieved by doing cardio or restricting calories.
Friends don’t let friends do high reps.