I must admit, I find it a bit weird that they assume things because it is how it "should" be as if the computer is morally obliged to be like that. We say things like "It should rain tomorrow" or "You should not steal"... implying either that there is some uncertainty to the statement or that it is a recommended thing to do.
Notice that with the use of "should" there is NO certainty - why I find it strange that developers even use the word "should" with reference to code. Developers should only be talking in absolutes when talking about code behaviour, and until they can talk in absolutes they should keep their mouth shut.
After all, they have the code in front of them; they can look at it - if it's a spec they're looking at, yes, the behaviour specified in the spec "should" (correct use) be what the code does. That is how things are setup, but if you have the code in front of you, I don't want to hear "should". Why take the risk of the "should".
Just today this is what happened. A method was taking a string and the string was called "status". Now there is also an Enum called "status", and the developer figured well, that "status" and the enum status should both have the same "toString". iow, the toString of the enum should map to the valid strings that the method understands... a big should. If that is the case then why does the method not take an enum.
Now, yes, it should be like that, but is it? In this context I'm not interested in should. This shouldn't cause a bug is just not good enough.
A cursory glance at the code should, oh sorry, can, often lead to the resolution of the doubt, and in this case, the assumption was proved wrong, causing a time wasting bug.
So in a development environment when one is asking how is the code behaving, one should never hear "should".