Why stupid ideas are important for innovation: Cadbury’s Darkmilk

Post by David Nichols, Group Managing Partner and Head of Innovation.

Watching Cadbury’s advert for their new Darkmilk chocolate reminded me of an innovation worksop I ran for the brand 15 year ago that illustrates the importance of ‘stupid ideas’ for innovation: starter thoughts that are only partly formed.

I was running the Cadbury’s workshop with my creative partner Matt Aver when an exchange between us came up what seemed like a stupid idea:

Matt: “What do you call chocolate that’s half dark and half milk?”

David: “Dilk!”

Dilk Chocolate became a working concept – the rich goodness of dark chocolate with the creamy taste of milk. But the idea never made it to the top of the pile on that project and I often wondered what happened to it.  Well, 15 or so years later, and Cadbury’s Darkmilk has been launched and is driving outstanding growth for the brand. “We’ve had really strong core growth supported through a number of initiatives such as Darkmilk,” commented Claire Lowe, Marketing Activation Director for chocolate for Cadbury’s owner Mondelez. Cadbury’s has become the UK’s no.1 Grocery brand, with sales of £1.7bn in 2019.

Stupid ideas are important for innovation and can turn into big business driving ideas if managed well:

  • 5% Rule – The idea of ‘Dilk’ got laughed at in the workshop because it sounded stupid. But it was a classic ‘5%’ idea: one you might think twice about sharing, as it not fully formed and seems a bit wacky. But such ideas are essential ‘fire-starters’ for innovation that need to be kept alive. They can connect with solid but unremarkable 35% and 40% ideas, adding up to the 80% concept we’re looking for (the last 20% is the polish you put on with your creative agencies).
  • 3 Buckets – never throw an idea away – keep it in the drawer to be fuel for your next project. Better yet, place your ‘failed’ ideas into three buckets in the office (or online): Gold (Great, progress to market), Silver (Good, but need work) & Bronze (the rest). Keep the Silver and even Bronze ideas tucked away ready to be brought out at the start of another innovation ‘sprint’. It’s a great timesaver and may yield a winner later on when the market, brand or consumer need has changed.
  • Live with bad execution – ‘Dilk’ was a poor name, I admit, and it probably clouded our judgement in de-prioritizing it. It’s important to make sure you are evaluating the idea, rather then reacting instinctively to a duff title.  


Innovation is about long stretches of hard work peppered with occasional moments of intense creativity. And sometimes a stupid, 5% idea is just the spark needed to fire that creativity.  I’m delighted to see how such a 5% idea lay dormant for 15 years but eventually came to life as ‘Darkmilk’, with a changed snacking environment and an improved name finally giving it wings to fly.