Not every deviation needs a supervisor, and if every small difference requires approval, people stop recording deviations and just work around the procedure. The useful line is whether the deviation changes the risk of the job or the outcome of a critical step.
Skipping a step that does not apply to this piece of equipment can be recorded with a reason and reviewed later, while changing an isolation, a setpoint, a sequence on a hazardous step or anything tied to a critical control should stop and require approval before the work continues. Defining that line in the procedure ahead of time is what keeps operators from having to make the call on their own in the middle of the job.