Earlier today, I was listening to The Ken interview the CEO of Fractal, where he mentions that he often sends ideas to his teams on what they ought to work on. Since he does this so often, his teams now wait 2-3 weeks to see if he comes back to ask them about it, and only then will they actually work on it. Otherwise, they treat it as a passing idea and don't give it much heed.

This process of waiting to see if it turns up again is a vague heuristic with a really small sample size. 

The better approach is to borrow a practice from good Product Management and size the opportunity in addressing such an idea - in fact, many such ideas come from customers, employees and various other sources. 

Yet, it is common to treat an idea coming from someone higher up with much more import than we would treat an idea coming from someone we don't consider as important.

However, the wait is a technique I follow in making some low stakes personal decisions like whether to purchase the latest model of a phone right now. 

But, the wait is a poor way to make high stakes decisions. 

It is much better to be a lot more deliberate about how we make them, rather than passively wait.