Of course it depends on the kinds of products you sell.
With clothes you more or less have to follow fashion.
But still: successful fashion designers create their own trends. People don't buy their clothes because they are like every other designer's. They buy them because they are unique.
I have designed about a dozen products that did not exist before I made them. So, there was no market yet, I created it. And there were no trends yet, I created those too.
- Before I designed them, no lip balm addict realized they could not do without one or more crochet keychain lip balm holders.
And before they saw the colour combinations I offered, they did not realize they like a holder in those colours.
- Before I designed crochet inhaler holders, no asthma inhaler user realized they needed one.
- Before Marc and I introduced keyboard cuff links (made from lap top keys) there was no recycled computer keys jewelry and nobody knew they where going to make the perfect gift for their partner.
This is what I mean when I talk about setting trends. Not picking a colour for a dress for a certain season, but creating a new market.