It's a 0.07 mm piece of plastic which has to absorb the forces caused by two moving bodies weighing > 100 kg together. Thus condoms do and will fail, even if properly fitted. The failure rate is estimated between 2% and 12% pregnancies per year.
Or to put it in more visual words:
If you had $ 200 000 in cash (that's the cost of a kid), would you secure it against theft with a 0.07 mm piece of plastic?
Or to put it in more visual words:
If you had $ 200 000 in cash (that's the cost of a kid), would you secure it against theft with a 0.07 mm piece of plastic?
It's insane that this is expected of men.