One key to the possible causes is exactly HOW they break.

There are two basic modes of failure.

1- a plate works it's way out to the end of the pin then falls off under load, causing the opposite plate to bend under load and slide the pin out. The most common causes of this type of failure is hard shifting under load, something that each "improvement" in shifting makes easier to do, and splicing via pushing pins back in which makes chains more vulnerable to plate movement.

2- plate fracture. This is rare because chain companies understand that this points right back at them, and make every effort to ensure that this is not a common mode of failure. Plate fracture can have a number of causes, from tolerance issues between the pin and hole diameters, to bad heat treating, failure to bake out ions after plating, and exposure to chemicals which can embrittle the steel. If you have plate fractures you should immediately make the chain manufacturer aware of the problem, because it's something they need to know and track. They may ask about how you clean the chain, but if diligent will log the issue and watch for more complaints of the same.

Twisted links usually don't lead to failure, but they do cause skipping which in turn can cause added stresses.

So, I don't believe there's anything inherent to the bike or it's drivetrain, but you need to try to analyze what's happening because you should not be breaking chains for any reason.