Look backwards from the finish

If a quantity doubles at every step, work backwards by halving. At 100%, the previous step was 50%. Before that, it was 25%, then 12.5%. A process can be much closer to its endpoint than its current percentage suggests.

This is why the lake-and-lily-pad puzzle works. If the lake is full on day 30 and coverage doubles each day, it is only half covered on day 29. The final days contain most of the change.

The Human Genome Project offers a real example of progress that initially looked slow. It began in 1990 with the aim of mapping roughly three billion DNA letters. Progress accelerated as sequencing methods improved, and the project was declared complete in 2003. The cost of sequencing then fell rapidly in later years—a related, but separate, trend.

A small percentage does not prove that a project is close to completion. It does show why a straight-line extrapolation can be badly misleading when the underlying process is compounding.

That is the pattern Dev needs to recognize before the clinic is already full.