Height, Width and Depth

I often like to buy things online, to save the inconvenience of having to find the shop that sells the type of thing you want and wander around from shop to shop finding one that has one that suits you. I much prefer to just type what I want and have the options presented to me so I can just choose one and buy it. This works perfectly well in some cases, but there are some confusing exceptions.

Things like media, where a digital download is quick and convenient, and things with standardised sizes, like men's shirts are fine. I can go onto the Rivers website and just tell them what sort of shirts I want and they'll send them to me and they fit.

But I've found that there are some things that they don't seem to want you to buy online. Oh, they'll sell them to you, but they seem to omit some really important information.

Take microwave ovens, for example. I thought it would be a simple matter to order one online, and I even had no trouble finding a place that would sell and deliver one. What they wouldn't do is tell me how big it was.

They'd tell me the internal volume in litres. They'd tell me the power and the technical specifications. But under no circumstances must the customer be allowed to know whether it will fit in the space allotted for it in their kitchen.

I was also looking for some glasses recently - drinking glasses, that is. Just ordinary tumblers. That was even worse than the microwave ovens, as many of the ones I found for sale online didn't even give their volume. And they're always photographed by themselves against blank backgrounds, so there's no possible way to get any sort of sense of scale.

How are you supposed to buy these sort of things if you can't tell how big they are? Do people just order stuff and hope it fits in their kitchen? How difficult is it to just include some simple measurements in your product information?