32 inches

is my waist size - or so I thought. Today I bought two pairs of shorts, without trying them on, as they were both marked 32 inch waist. Now, I got them home and tried the first pair on. Fine, fit no problem. I then took the second pair from the bag. Please note, I did not at this point eat a full English breakfast, or several pies, or bodybuilding supplement. I put them on, or rather, I pulled them up to my waist, but I could not do the flies or the button up - and not just hat they are tight, or that I have to breathe in to get them on. There is a good 2 inch gap between the button and the hole. I will return them tomorrow and get a pair of 34’s (after having tried them!). But can anyone explain this to me - I understand that trousers have different cuts, but shorts?