PlayStation Track Monitor Speed Limits

Hey folks,

just a simple Question.
The Track Monitor shows the upcoming speed limit above the line. Sometimes there are limits below this line. What does these limits mean to me?

Thanky in advance

 

nothing. they save up space for when they are too close on the display so they don't overlap and get unreadable, for example

 

Ok, this is an argument! So easy, so clear. Thank you