A metal mount is generally superior to a plastic mount as it is more durable.
The device is protected with extra seals to prevent failures caused by dust, raindrops, and water splashes.
A longer maximum focal length allows you to focus in on a small part of a scene, and offers a narrower angle of view than shorter focal lengths.
We consider a lower weight better because lighter devices are more comfortable to carry. A lower weight is also an advantage for home appliances, as it makes transportation easier, and for many other types of products.
A shorter minimum focal length allows you to get more of the scene in the photo, and offers a wider angle of view than longer focal lengths.
It comes with a lens hood so that you don’t have to buy it separately. These are used to block strong light sources, such as the sun, from the lens to prevent glare and lens flare.
The front element doesn’t rotate. This is important if you use filters, as some such as polarising or gradient filters have to be orientated a certain way.
A prime lens has a fixed focal length. In general, these are sharper, with a wider aperture.
The diameter of the front part of the lens, where the filter threads are placed. The lens diameter doesn't influence image quality, but it is crucial to take into account when buying filters. Usually, lenses with larger diameters are more challenging to handle and substantially more expensive.