Each time you miss your training, you lose twice. One for being behind your schedule, and another for being behind your opponent.
In other words, not only are you behind on your schedule, but your opponent is ahead of you.
This changes your perspective.
But the reason why being behind schedule is bad is because you are behind your opponent. They don't count twice.
The only way this makes sense is if you actually regress during your missed practices. That way, not only do you miss 2 practices, but it takes you 2 more practices just to get back to where you were before. Then it's like 4 missed practices total.
This is a very interesting and motivating point. But I do not think it goes into the causal matrix.
It may be behind your schedule, behind your opponent, and behind the refrigerator. But you don't simply add everything that your training is behind.
Your training schedule prepares you for your opponent. Being behind your schedule is already equivalent to being behind your opponent.
That said, changing one's perspective can be very beneficial.