stumbly warm start

Sometimes on warm start it cranks weird. For example on a cold start it always rotates 5-6 times at a normal, even pace before it turns on (in maybe 1.5 seconds), whereas on a quick warm restart, like after gassing up, I'll sometimes hear the cranking noises but over less than a second and at a rapid, uneven pace, like something is out of sync. But not always. Once going, whether cold or warm, the engine runs normal, idles smooth. It has done this for at least a year or maybe multiple years, I don't remember because I accepted it as normal.

Is this a cylinder with low compression, fuel injectors, ?