Sometimes we expect everything to happen straight away. But improvement takes time. The chances of turning up to parkrun each Saturday morning and knocking a few more seconds from your PB is unrealistic.
You need to focus on the process. Introduce a strategic training plan that will help improve your running over a sustained period of time.
Often you’ll run a new PB when you least expect it. I’ve had PBs at the end of a long training week and in races I had no intention of setting new personal bests.
Stick to the plan, work hard, be consistent, remain patient and the rewards will eventually come your way.