Adding this for visualisation - it may be more confusing than it’s worth, but if you look at the bandwidth around which two consecutive steps can exist (looking at the two lower bars representing all the places where ‘2’ and ‘3’ can be (with quantize off) you can see that they can be close or far apart, but there is a limit to where step ‘4’ can then exist as its window is later on - so depending on what the sequencer is fed there’ll be notes dropping out if there’s no room left on that step’s possible window to capture
picture in this post may or may not help