Seeking clarity on Reddit, they turned to motoring specialists for guidance after noticing several "small dents" embedded within the tyres of a neighbourhood bus. ‌Their inquisitiveness led them to post on the social media platform's bus subreddit, where they asked: "What is the reason for the small dents on the side of Arriva bus tires?" "The sides of bus tyres are extra thick for this reason." While a further Redditor elaborated: "It's a visual indicator to show if any of the wheel nuts are starting to come loose. If wheel nuts are over tightened they can get hot expand and snap off.