09/12/2013 05:21 pm ET Updated Nov 12, 2013

Apple's Gamble on Fingerprint Scanners May Take a While to Pay Off

Marissa Mayer doesn"t use a passcode on her iPhone. As the CEO of Yahoo, one of one of the world's largest technology companies, she probably has some pretty important information sitting on her device. And although she has to deal with the constant threat of being hacked at any time, it's just too inconvenient for her to enter a few digits each time she wants to send an e-mail.

That's why she and so many others are eagerly awaiting the newly unveiled Touch ID feature that will allow users to use their fingerprint to unlock their new iPhone 5S.

While the news has been met with a mix of excitement and suspicion in the media, Apple's stock price hasn't fared quite as well. It seems that investors are not yet convinced that the company will be able to revolutionize mobile security. Whether its the failure of similar initiatives in the past, questions over security, or the specter of the "Apple Maps" failure that seems to loom over every new release in a post-Jobs era, Touch ID will face a considerable amount of challenges before it truly becomes mainstream.

To their credit, there's a lot of things that Apple got right. From the high quality of the sensor, to the seamless integration into the home button, design-wise, it is one of the most elegant uses of biometric technology in a consumer device thus far. They were able to sidestep many of the largest issues related to security and privacy by encrypting and storing the fingerprint template locally. But the best decision they have made also has been the most controversial: Apple has delayed the much-hyped biometric payment revolution.

They have set the bar purposefully low. Instead of trying to change the way we authenticate ourselves online, they are positioning this as a solution to security/convenience tradeoff involved with the passcode. Even so, it is not clear that they will succeed at this.

In reality, fingerprint scanning can be unreliable and difficult to use. The problem with biometric technology is that it is hard to know how it will perform outside of controlled conditions. Fingerprint scanners often wear out over time, and when they come into contact with water, sweat, and dirt, they don"t perform nearly as well. The elderly, which makes up some of Apple's most dedicated fans, and those who do manual labor are known to have worn-down prints that are difficult for machines to read. The problem then isn't that Touch ID will let others in, but will keep you out.

Unless it is a near-perfect experience, don't expect this new feature to make much of a difference for the half of iPhone owners that don't bother to lock their phones. If Touch ID doesn't work how users believe it should, they will simply ignore it and forget about it. But for Apple, that will mean an enormous business opportunity lost.

If the company can't get users comfortable with the idea of scanning their fingers to access their information, then how will they convince customers to use Touch ID for every online transaction?

By only enabling Touch ID to be used for unlocking phones and making iTunes purchases, Apple has given themselves the ability to iterate and learn from their mistakes for future products. Although they are taking some heat right now, it will likely prove to be a wise decision for their long-term strategy. If Apple were to open the floodgates to app developers today, there would be short-term gains in valuation. But it could also backfire and ruin the feature's credibility with users before it has a chance to grow into something significant.

What Touch ID represents is much bigger than just an authentication system, it is a fundamental change in the way we interact with our devices. There is a long road ahead for biometric technology. There are many issues that must be overcome before it is accepted as something that is trustworthy. The death of the password has been greatly overstated -- but the race to replace it is only just getting started.

This article originally appeared on Forbes - Disruption and Democracy