Speaking to the driver, he admitted he was distracted by another vehicle. He was very apologetic, hence why I’ve blurred his registration and face. Hopefully it will be a mistake that he won’t make a second time.
This highlights the importance of drivers (and indeed all road users) to not get distracted and be fully aware of what is going on around the vehicle. Never overtake a slower moving vehicle when intending to turn left (in the UK, right in other countries) and always check mirrors to check it is safe to move before signalling and making the manoeuvre.
It also highlights the need for proper cycling infrastructure. With a protected cycle lane here, the entrance to the petrol station could be narrower and at a sharper angle, forcing a slower and more considered turn by drivers.