If you are trying to follow a specific course or route, I recommend turning off the auto recalculate functions. If you are not paying attention, make a wrong turn, it may significantly change your route particularly in urban/suburban areas until it gets you back on course. You miss a turn, the unit recalculates without you noticing, you look down at your Garmin and you will appear to still be on course. I recommend Prompt or Off for in the course or route settings. The Garmin manual does not go into detail so you will need to look at your unit. If you are riding with a group this will keep you from meandering off course.

Route Settings - Select Menu symbol > Activity Profiles, select a profile, and select Navigation > Routing.

Course Recalculation - Automatically recalculates the route when you deviate from the course.
Settings:
Prompt with Auto Re-route
Prompt Only
Auto Re-route
Auto Pause

Route Recalculation - Automatically recalculates the route when you deviate from the route.
Settings:
Prompted
Automatic
Off