What's the difference between "fixed length" and quantize function?

Cubase
1

What’s the difference between “fixed length” and quantize function?. Thanks

2

Could be wrong without checking first, fixed length will make notes say, 16th in length, whereas quantize will extend/shorten end of note to nearest 16th. Both depends on what division you have selected in quantize panel.

3

Almost…right!
Fixed length: Will make all selected events the length according to the selected quantize value. So it won’t move the start of the events. It will just extend or shorten the end of the event to fit this value.
Quantize: Will move the ‘start’ of an event to the nearest value set in the quantize box but will not affect the length of the event.