What is the purpose? Well back in January I started "Couch to 5K." I completed the program a few weeks ago and even finished one 5K race. Finished in 37.49 which is slow, but hopefully, soon, I will get that 5K time under 30 minutes. On a positive, this week I logged 22.5K.
By the way, I'm 40, 250LB and a million times better at racing motocross bikes than running by foot.
So basically, the purpose is to log my running progress.