Introduction
A deep learning project quickly turns into dozens or hundreds of runs: different learning rates, architectures, augmentations, data versions, sometimes each taking days on several GPUs. A week later, someone asks "which settings gave that 91.3% result?" and nobody remembers. You rerun the "same" experiment and get 89.7%. A cloud machine is reclaimed halfway through a three-day run and everything is lost.
Three habits prevent this:
- log every run automatically, with its full configuration;
- compare ideas fairly, over several random seeds, not single lucky runs;
- checkpoint long jobs so they can resume exactly where they stopped.
Think of a scientist's lab notebook: every experiment is written down with its date, ingredients, conditions and results, so anyone can repeat it and trust it. In deep learning, tools do most of this note-taking for you.