Those are skinned items, you can make them say whatever you want.
Also "Full" is a word intended for measuring volumes. It should not be used with arbitrary numbers. People decided to anyway, since you couldn't use "maximum" in this situation (absolute term). It now has a colloquial meaning applied because of its improper use.
1254 vs 1255 combo, no misses, no breaks. That means 1 of your hits did not escalate the multiplier, but still received a multiplicative score count. I made it clear that all hits received an upward-scaling multiplier. The difference is that peppy decided to introduce a penalty for letting go of a slider early instead of breaking your combo. The previous combo multiplier is still applied. All hits received 1255 stages of a combo multiplier, 1 of them repeated itself. It's a much smaller difference.
That 20$ is not actually 20$ unless you BREAK your combo. It's worth less than 1$ in the case of a slider-end mistiming, but it is not this reduction in combo that affects your score so much either... it's the fact that you are receiving a 100 and not 300 for each one. But if you broke your combo, then it's 20$. Even then it's more complicated than that because multiplicative combo means those last 20$ after a BREAK could impact your score by 100$.
100$ vs 1$.
A glass of water is a full. A glass of water is filled to it's maximum (i.e. "filled to the brim").