Three stressful careers, and the consequences of failure:
(a) City financier / trader / project manager etc. Make a mistake, it costs your company money - perhaps serious money. You might well lose your job over it, other people might lose theirs in the fallout. I've seen it happen.
(b) Doctor / surgeon. Make a mistake, the patient on the operating table could die.
(c) Airline pilot. Make a mistake and you, your aircrew colleagues, your hundreds of passengers and any number of people on the ground could die.
Most occupations these days are stressful. That's modern life for you. What separates this one from (a) and (b) is that the consequences of mistakes are several orders of magnitude higher than any other career I can think of. Which gives one pause for thought on a dark horrible night.
Having worked in two of the above professions, I know which one I prefer. But don't anyone think that this job is all pushing buttons and impressing the hosties. It has stresses and strains which simply do not compare with any other job.