Depends on what you are chasing and how you are vaping.
I believe the XMax is a conduction vape with a ceramic heating chamber. This should sustain flavour for a few hits at a medium temp. Some people will dump the AVB (Already Been Vapes) material once they start to get the burnt popcorn taste. Others will bump up the temp to cache as much out of the AVB as possible.
Running at lower temps tends to give you a lighter coloured AVB and produce a clearer head high.
Running the vape at a high temp will cause the flavour to drop off quickly but yield a more heavy stoned body buzz.
You can temp step by starting at a low temp to preserve flavour and ramp up the heat towards the end to get a more balanced result.
Some people like to hit a bowl at a low heat and for a clear daytime high and the dump the AVB so they can run it through the vape again later at higher temps to get that lazy stoned effect.
If no more vapour is being produced by the vape while on max temp then the material is usually done at that point. Some folks with multiple vapes may try to walk out any last actives by transferring to a harder hitting vape for a final hit.
It's all guidelines and recommendations, really you just need to have a play with the vape and see what suits you.