Why succulents can be so difficult to identify

This is Aloe Zebrina, an extremely variable species in nature, growing in full sun in my garden in a bucket, waiting for the day I have finished my building and can finish cleaning the rubble and create my rockery. Because of sun stress, the leaves are compact and quite red. When succulent leaves are reddish, it shows sun-stress although the plants can easily hand that amount of sun without being sunburned and I prefer to keep them colourful. This particular plant was given to me by neighbour as an offset but it is hard to believe that this is a clone of this plant:

The grass-green aloe on the left is the parent of my plant but it is growing in partial shade, so the leaves are etiolated, meaning they are long in response to light-starvation and it is as green as possible to utilise the amount of light that is available.

People who didn't know better might think that the bottom plant is an Aloe Vera but the different looks are just caused by different growing conditions, my offset was also long-leaved and green when I got it and I had to get it used to more sunlight gradually so that it would not be badly sunburned. More than a year later, the plant is compact and resembles plants found in the wild.

Just to confuse the picture, the plants below are also Aloe zebrina, found growing in its natural habitat at the end of the dry season. As you can see, they also survive being burned in regular grass fires. I need to take a look and see if the ones on the hill are also currently flowering.

The same plant after a little rain:

Another specimen I have growing at home. This one alternates between grey and green, depending on the season