Values from bypassed nodes?

[phazei]

I've found that some nodes that accept a value, some of them can take a value through a bypassed node, and others don't receive any value of a bypassed node.

Does anyone know what differs in the code when receiving the input value?

In my node I simply get the value from def process(self, input_text), but I don't do anything complicated like accepting anything and typing on the fly.