Training loss falls. Which checkpoint do we keep?

Training and validation lossIllustrative loss curves. The values are also listed in the table below.0.20.30.40.50.60.7123456EpochLoss (lower is better)
TrainingValidationRing: best checkpoint

Illustrative losses, not a measured training run
EpochTrainingValidation
10.700.60
20.550.50
30.430.51
40.340.49
50.280.50
60.230.52

One validation check per epoch. Any strictly lower validation loss counts as an improvement; min_delta = 0. Checks after stopping are not processed.