Personally, I use it to determine what habits to avoid or which ones to adopt in order to feel more rested. I had always heard the common dos and don'ts for how

Personally, I use it to determine what habits to avoid or which ones to adopt in order to feel more rested. I had always heard the common dos and don'ts for how to improve sleep. But never really felt that motivated to improve it. Once I started tracking my sleep, I realized how bad certain habits were having on my sleep, and ultimately how I felt the following day. Being able to quantify sleep quality provided me with data that I can use to try to make myself healthier and learn about my own body. Sure, I could make the same changes without having that data. But personally I wouldn't be as motivated to continue with certain habits. Others may differ. But the same also applies for me with fitness activities and other health metrics. Seeing progression and improvement encourages healthy habits. And having the data from it is just a way to measure progress or regressions.