For all the talk around ethics in influencer marketing, it's shocking how little advocacy there is for authenticity as it relates to exclusivity. As more and more influencers land products in the social spotlight, brands are increasingly calling for brand exclusivity -- for 30, 60 or 90 days, or even six to twelve months, and sometimes longer.

On the surface, this request makes perfect sense. But requiring exclusivity is a terrible idea. Here's why.

It unfairly limits professional opportunities

First, it's unfair to require professional influencers -- people who make a living working with brands -- to turn down other paying gigs. Exclusivity reduces the number of potential employers for influencers, usually without offering them opportunities or compensation to make up the difference.

It erodes credibility

Second, and probably of greater importance to the brands, asking an influencer to only use one product, and not even mention competitors, erodes the credibility of the influencer with his or her audience. This in turn makes the program less effective, and in some cases may even damage the reputation of the brand.

This can sound counter-intuitive to some, especially if you come from a traditional media/digital ad perspective: What if a competitor's ad looks better or offers a better deal? What if competing ads confuse the consumer? An influencer who works with competitive brands will only add to the confusion, right?

Not, exactly.

Authenticity means self-control

Marketers want to work with influencers because they know influencers have a special connection to their readers, and their readers love them. Their readers listen to them, not the brand. When a brand tries to force an influencer into behaving like an ad, readers immediately sense the lack of authenticity and turn away. Requiring exclusivity makes influencers behave like ad units instead of people -- and that results in a fake, failed campaign.

Marketers should keep in mind that blog or Instagram (or Facebook or YouTube, etc.) posts are created by the influencer, not the brand. An ad is always experienced as "something the brand is directly telling you." By contrast, when an influencer shares carefully crafted sponsored content, the reader experiences the influencer's interpretation of the brand messaging -- and that's the key. The influencer has worked hard to build her audience's trust, and her audience knows this. Any brand messaging is interpreted as a peer-to-peer recommendation. Besides, in real life, people use many brands and services, including some that are competitive.

Real life isn't always brand loyal

In real life, you may love a certain brand in a certain situation, and use something completely different in another. For example, you might use brown sugar for baking chocolate chip cookies, super-fine sugar for making raspberry sorbet, and an artificial sweetener for a big pitcher of iced tea. All three of those items could be made in the same kitchen, on the same day. That's real life.

If an influencer only ever uses one brand, it looks fishy; it looks fake.

To take it a step further, influencers are able to influence their audiences because they've built an expertise, usually by trying a wide variety of products, and sharing the pros and cons of each. They're experts precisely because they've tried and evaluated many different options. This is something an ad unit cannot achieve.

A beauty blogger usually will advocate one brand of mascara and another brand of lipstick -- and probably combine multiple brands of moisturizer, primer, foundation, and eyeshadow. Outside of a branded store environment, real people use all kinds of products, from drugstore to luxury brands. Readers both understand and expect to see this kind of real experience. To curtail that natural product variety by requiring exclusivity makes the content, and the context, seem fake.

Authenticity beats exclusivity

It's important to give influencers the flexibility to do their jobs effectively. It's also important to respect the authentic relationship they have with their audiences, and trust both the influencer and reader to accurately judge what they're reading. Consumers understand that a professional can have a transparent, sponsored relationship with a brand, and still give an unbiased, real opinion.

Besides, if you believe in your brand, don't you want it to be tried, tested, and compared to the competition? Don't be scared. If your influencers also believe in your brand, you're in excellent hands.