A bit of heatsoak can really mess with engine starting, as the perceived air temperature is out of whack. I'm thinking about minutes rather than hours between starts though.
An underperforming spark plug/ignition coil can lead to a weak start too. If it continues I'd think about inspecting them for signs of fouling, corrosion or arcing as well as checking battery condition under load. Shame the plugs are tricky to whip out.