Why would an aneurysm (a widening of an artery) be especially subject to ruputering?

I am thinking the pressure is greater than what the artery can handle.
How do I express this?

Thank you.

Wider areas of a blood vessel experience lower flow velocities and (because of Bernoulli's effect) higher pressure.

The walls of the expanded aneurism may also be thinner than normal sections, but I am not that kind of Dr.