Know what you are capable of. And knowing your initial capabilities will allow you to set realistic goals. Essentially, you will allow yourself to set clear expectations. And the more you create realistic goals, you will have created "attainment benchmarks". Then as you attain your goals, you can re-calibrate them.
And THEN, you will see the tangible results.
So, an example. Let us say you are touching the rim of a basketball net, but are not yet dunking with a ball. Create goals like increases in hip thrusts, front squats, and deadlifts. Create goals on adding plymoetrics to your workout. THEN, test weekly, your vertical.
Once you feel you have gotten the necessary strength, you can goal yourself to dunking.