A brighter display with higher contrast is more likely to work reliably with certain barcode scanners. For example, I sometimes struggle to get my Tesco Clubcar

A brighter display with higher contrast is more likely to work reliably with certain barcode scanners. For example, I sometimes struggle to get my Tesco Clubcard QR code (edit: actually an Aztec code) to scan on their old (red laser) self-checkout machines with my iPhone, but on my Apple Watch it displays brighter and seems to work more reliably.