Haworthia cooperi is a stemless leaf succulent, a dwarf plant forming rosettes on the ground. The plant is highly variable. There are some with short, broad leaves in tight rosettes, others with loose rosettes and short or long, broad or narrow leaves. Leaf tips vary; some have awns or acute tips, others have obtuse tips. Leaf margins vary from entire to serrated, and so on.
Too many differences and too few similarities may have been taken into account. The splitters had their field day or too many days, naming about many varieties, thirteen of which are currently listed by SANBI. So, the lumpers may retaliate, undoing some of it, a bit like a conservative comeback. Overdoing separation may be followed by a turnaround into a closer huddle. So watch this space!
Fortunately, there are the techniques of molecular biology today that supersede plant appearance as the main classifier, resulting in taxonomy based on common ancestry. A couple of PhDs later and all should be well.
Until another high curiosity creative youngster squints at an innocent flower, pondering a new angle involving uniqueness, like parents contemplate the attributes of their children. If the professor is convinced, a few years of work may follow to upturn the applecart once more. Grey-haired back garden buffs grumble about having to revise the ten botanical names they remember yet again (Smith, et al, 2017; Scott, 1985; http://redlist.sanbi.org).