By and large, I find the male CC on BA more courteous than their female counterparts, but I've yet to find any of them being rude.
It's fair to assume that if the person with whom the CC dealt with one, three, five, seven or ten minutes earlier was ghastly, even if you're at your most charming, that horrible little grey cloud will follow her around.
Trying to stand up straight on a narrow wobbling walkway, trying not to spill other people's drinks whilst dodging inebriates and being ogled to boot is just fine for me on Christmas Eve, but not five times a day, four times a week.
The demeanour of CC is palpably different earlier in the day than that dreaded last leg home. Sometime they'll be weary and grumpy, others will be looking forward, as I am, to getting out of that tin can.