The help tip (?) on that section of XO (xertonline.com) links to this article –
Program Type – Xert (baronbiosys.com)
TL;DR – As you drag the slider to the right the weekly change in estimated hours/week increases/decreases (or stays the same) according to the ramp rate (IR) you have defined under Goals. Try changing IR (improvement rate) to Maintenance (ramp rate = 0), save change (Update Advice), and you’ll notice no change to weekly hours when you drag the slider.
Reference –
Beginner’s Guide: Improvement Rate – Xert (baronbiosys.com)