My wife Kathy is a huge Sherlock Holmes fan.

She's got all the books, we've been to 221b Baker Street (more than once) and we watch any TV show or film with a vague reference to the great detective.

So a few years ago when both CBS and the BBC launched new series featuring Holmes we started watching both eagerly.

Initially, we thought the BBC's Sherlock with Benedict Cumberbatch and Martin Freeman was much the better show. Better, more satisfying, more intricate plots. Elementary with Jonny Lee Miller and Lucy Lui was good, but just not at the same level.

A few years later, after three series of Sherlock and a series and a half of Elementary, we sat down again to watch Jonny and Lucy do their stuff.

And at that moment I realised that while I still thought that Sherlock was a better show, I had warmer feelings for Elementary. It felt like inviting old friends back into my house.

It's not that the characters are more appealing. Lee Miller's Sherlock is just as abrasive as Cumberbatch's.

It's just familiarity.

There had been only 9 episodes of Sherlock in nearly 4 years. We'd watched 34 episodes of Elementary in just 18 months.

The regular, consistent good of Elementary had overtaken the infrequent brilliance of Sherlock.

I think marketing works like that too. If you look at email marketing, for example, too many people try to get by with a monthly newsletter. Meaning that if they want to be remembered, they have to make a huge impact each time.

Meanwhile, people like me are mailing much more regularly. Just drip, drip, dripping into our subscribers' consciousness.

Regular consistent good beats infrequent brilliance.

Bear that in mind next time you're working on your marketing.