The link is a good presentation about Dark Patterns, only 20 minutes long, so worth a watch.
"Dark patterns" are defined as marketing anti-patterns that may bring you a direct return (more users, more money, etc) but risk your brand along the way. Examples include bait and switch, sneaking things into your shopping basket, disguised ads, hidden costs, etc.
Should you use dark patterns? I guess it depends. Facebook notoriously used the Friend Spam to fuel its explosive growth. And, of course, they are by definition guilty of Privacy Zuckering. However, it doesn't seem to have hurt their brand all that much.
This is a controversial point, but I would say that depending on your market, dark patterns may be essential survival tricks that will make or break your business. Could you compete in the highly competitive domain registrar market without dark patterns?
Taking a leaf from the "real world", supermarkets like Walmart or Tesco use many tricks to help increase their sales, including laying out the store in a way that will be likely to increase your spend, and this may have been controversial at some point in the past, but it is now accepted as standard business practice.
Perhaps the smart move is not to discard dark patterns entirely, but to become more savvy at knowing which ones work for your industry, and how to implement them in a way that won't damage your brand with the majority of your users.
The talk makes a great point that if you are going to be using dark patterns, you should do so deliberately, not by mistake, and with full awareness of the impact it may have on your brand.
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