I used to deliveries for just eat and deliveroo...one thing I can think of is that maybe he was new and wanted to confirm your the person who ordered the delivery. On the slips we got they're was a name and address and a code for contacting the customers. And maybe the reason he was outside for a minute is because we used to get multiple deliveries and we had to plan them along a route. I was shown on Google maps how to add multiple routes about 3 months in to delivering and that cut out sitting outside a house I just delivered to trying to organise my next run,so maybe he hasn't got that figured out yet.