The direction you’re facing is very important information, but your device might not be giving you an accurate reading if the compass isn’t calibrated well. This is why Google replaced the arrow with a beam in the latest version of Google Maps.
The new location icon has a flashlight-like beam pointing in the direction you’re facing, and its width indicates how accurate the direction is. This is definitely a better way of showing this info since it’s not misrepresenting the accuracy of your device’s compass.
If you’re getting a really wide beam, it’s an easy fix. Google says moving your device in a figure eight a few times should help calibrate it and give you a more accurate direction. Give it a shot next time you’re out!