Profiling is no different than running an experiment, which relies on your ability to create reproducible profiles with your inputs, with each data sampling remaining constant. If you start your data run on the bench and manually load the profile into the Reflow oven, it is unlikely that you will get the exact start and stop point for each run. Take care to start and stop in the same physical location each time.
To ensure repeatability, profiling software should, at a minimum, include both automatic distance measurements and temperature triggers, rather than manual start and stop points. The air thermocouple feature of the KIC system does away with the need to manually trigger (on/off) of the profile run, eliminating a step that can potentially invalidate your profile run.