A Marmite watch is one that divides and indeed polarises opinion. You either love it, or hate it. Much like Marmite.
Among the idiosyncrasies of British cuisine is Marmite, a strong, dark paste made of yeast extract and traditionally spread on bread. However, unlike the quintessentially English delicacies of fish and chips or afternoon tea, Marmite provokes very strong reactions. Its distinctive, very powerful flavour means that what is nectar to some palates is poison to others, and its capacity to make people smile with pleasure or gag in sheer disgust has had such an impact that, remarkably, the word marmite has now been adopted as an adjective. In informal British usage, marmite is being used to fill a gap in the lexicon for describing something that people either love or hate.
If something is described as marmite, then there's no way you can be indifferent about it or express minor shades of like or dislike. No, if it's marmite, then its very nature forces you to firmly sit in either the 'love it' or 'hate it' camp. Of course among the most obvious candidates for marmite status are artistic creations, things that people are conventionally permitted to have strong feelings about without any fear of recrimination, so that the word regularly crops up in descriptions of music, architecture, theatre or cinema. Correspondingly, though marmite would seem a contentious way of describing a person, it does pop up in descriptions of actors, musicians or other celebrities whose performances provoke strong positive or negative reactions. That said, a brief analysis of web-based evidence suggests that marmite can modify a broad range of other concepts, abstract or concrete – mountains, golf courses, managers, accents, book titles, cars and electronic games are just a few of the things that I've seen described as marmite.
And now it can be used to describe watches too!