Idea interruptus happens when you are happily focussing on developing an idea and along comes another idea out of the blue. This creates an immediate decision: do you stop what you are doing and entertain the new idea, or do you ignore it and keep working.
The problem with stopping the flow is that it takes time to get back to what you were doing, and there is a cost to losing momentum. In creative work it often takes time to generate focus and get into flow. The last thing you want is to interrupt your own workflow.
But the problem with ignoring the new idea is that you might lose it forever. Ideas are precious, and losing them is a crying shame. They may never come back. This explains the tension you feel when the new idea emerges.
Another way to think of this: it’s a battle between the Explorer and Artist. The Explorer wants to keep exploring, knowing that the more ideas you consider, the greater the likelihood of landing on a great idea. But the Artist is feeling the pressure to create, and knows that the sooner you get to focused work, the more time you will have to generate something that really works.
Best practice is to always have a capture machine with you when you work. Then, when the new idea interrupts your flow, you can just quickly capture the new idea and get back to work.
Why It Works
Because you capture the idea when it occurs to you, you never lose it. And because the interruption is so short, you can get back to work right away without losing very much momentum.