Fashion is a fickle business – but its giddy younger sister, the accessories game, is even more so.
Perhaps the business of jewellery, scarves, watches and hats could even be described as capricious.
Who could have predicted that this summer, adults who are otherwise perfectly sound of mind would willingly sport brightly-coloured elastic bands on their wrists, after succumbing to the loom bands craze?
Pete Boyle is one man who has cornered the accessories niche, and not a loom band in sight, in his phenomenally successful Argento business. It has become so ubiquitous on our high streets that it's easy to forget that its founder is a man from Strabane who seldom draws attention to his success.
Mr Boyle started as a young entrepreneur selling mirrors at the Ballyshannon Folk Festival in Donegal.
He went on to sell jewellery from stalls at festivals and on beaches, and discovered a knack for spotting what might sell well.
Argento has popularised brands like Pilgrim and Pandora, and is now branching out into manufacturing its own jewellery. But Mr Boyle vows that he never stands still in business, and his trajectory reflects that.
Many of us can remember him selling jewellery from a stall in Belfast city centre.
When street selling was banned, he graduated to a tiny shop in Castle Street before growing more and more with every year – and every trend he was able to capitalise on. As Mr Boyle himself points out, his new megastore will look out across at the Reform Club, a bastion of Ulster business, and is a stone's throw from his first shop. A very nice niche, indeed.