Sitting in the back departing Warsaw about 4 weeks a go on a day with flurries of snow, some heavy, and outside temperature around 0C, I felt very relieved that our Captain elected to take the full de-ice on offer near the holding point, while some others did not and taxied past while we joined the queue. It seemed to be about 50% taking it, 50% not, but that's only a guess.
I understand that those who did not probably had no need for a de-ice for one reason or another, quite legitimately. But I did find myself wondering if cost and/or slot times might have been a small factor in the decision, among others, for one or two. Perhaps those who took it had an insurance de-icing contract.
And then I thought that no-one is suicidal, regardless of the pressures, and they all know what they're doing.
But is it easier to persuade yourself, when it's marginal anyway, that it's OK not to take de-icing if you are under pressure to keep the schedule and minimise cost?