"Another aspect is the principle of behavioural consistency — consumers and humans are all creatures of habit, we tend to behave in a certain way and exhibit the same behaviour. Subscription boxes are a pleasurable thing, they arrive at your door once a month, so people keep their subscription going.
"The other thing retailers use is the scarcity principle — the fear of missing out. What some services are doing in America is offering boxes curated by celebrities and the premise is this isn't going to last forever, so you have to sign up quickly to get this box."
Grimmer stressed she was neither for or against subscription boxes, as long as consumers were getting high quality, good value products — but she said it was important to understand the psychology behind why we're likely to get hooked on them.
"You just need to be aware of the psychology of why you might be wanting these boxes, and you need to be aware of the fine print. You hand over your credit card details in order to have a recurring subscription, and sometimes people don't read the rules around minimum delivery or cancellation, so it's a case of buyer beware," she said.
"Some services also want to tailor-make a box for you, so they ask you to fill out a detailed questionnaire, and while that helps them curate your box, you need to be aware that the information collected can be shared with the brands featured in the box."