Realistically, no day is 100% good or 100% bad, instead it is a blend of both good and bad moments.
Some days the good outweigh the bad, and others the bad outweigh the good.
But that doesn’t have to make it a good or bad day, it just makes the day a combination of both good and bad moments.
The reason why it’s important to learn the difference is because life is experienced in moments, not days.
If you say the day is bad, you have to wait a whole 24 hours for the next chance at having a good day.
But if you say it is a bad moment, then you have the opportunity right there and then to make the next moment a good one