No one can tell the future. Some people try to do it by looking at the past. Investing has a mantra for that, "Past performance is no guarantee of future results."
The sad part is this never changes and never will.
The sad part is this never changes and never will.
There are situations that are way more predictable than the stock market. We as humans use the past to successfully predict the future all the time. For example we predict that we won't be able to walk through walls not because we understand how atoms bounce off each other but because we experienced not being able to do that.
Software Development is certainly more predictable than the stock market but less predictable than the walking through walls example.
In a stable team, often past performance is a strong indicator of what will happen next. It's not perfect, black swans can occur, but no one is asked to predict if your project will get cancelled for example.