After news broke last week that hybrid law firm Atrium would be shutting down its software startup, CEO Justin Kan told TechCrunch that the company "did not figure out how to make a dent in operational efficiency." But it may not be legal tech providers that are coming up short.

While there are plenty of solutions on the market geared towards automating tasks such as brief-writing, pulling cases or even fielding basic client questions, getting work done faster flies in the face of the traditional billable hour model that continues to sustain many a law firm. In fact, the real answer to why technology can't kill the billable hour may be exceedingly simple: Attorneys—and even some clients—don't want it to happen.

Joe Dewey, a partner at Holland & Knight, indicated that the firm struggles with just how much of their technology and efficiency gains to showcase for clients. It's often negotiating the sometimes tenuous balance of positioning yourself as the law firm of the future and shooting yourself in the foot.

"You may not want them to know how well the technology works because if they see how dramatic the time savings are, all the sudden you run the risk of them saying, 'Well why am I paying you this much money?'" he said.

There are other practical implications to consider as well. Firms shelling out the salaries for large practice groups full of attorneys, for example, don't want team members sitting idly with nothing to do because a machine has already accomplished a task for them.

This is typically less of a problem with smaller firms who retain modestly sized staffs. Legal consultant Brett Burney also noted that smaller firms tend to handle areas of the law like estate planning, family law or trusts that lend themselves towards automation. In his view, they are also more likely to step away from the billable hour, although that attitude may not be trickling upwards in the direction Am Law 100 firms any time soon.

"I wouldn't know when a large law firm would look at a small law firm and say, 'Hmm, that's interesting what they are doing.' The only time I would maybe see that is if a large law firm loses business to a smaller law firm," Burney said.

To be sure, flipping away from the billable hour model could require a significant structural change inside firms beyond just how they charge for their services. Catherine Moynihan, associate vice president of legal management services at the Association of Corporate Counsel (ACC), pointed out that law firms also use billable hours as a metric for employee performance. However, she believes that may change as Millennials become increasingly prominent in the legal workforce. Not only does that demographic tend to be more interested in results versus time, but there's also robust interest in opportunities to work away from an office.

"And so that also forces the hand towards being more flexible, being more creative about how performance is measured, which I think will help sort of grease the skids towards shifting away from the billable hour," Moynihan said.

However, it's not just attorneys who may be reluctant to leave the billable hour behind. Dewey indicated that his firm occasionally presents an alternative fee proposal to a corporate client only to have it shot down. One possible reason? Clients who have been in the profession a long time may be just as attached to the comfort and familiarity of the billable hour as attorneys.

"They feel it's a somewhat fair metric to evaluate a lawyer's time. And I think related to that is the fear of paying too much, that the law firm will somehow get the better of that bargain or a deal such that maybe the time would have come in significantly lower than the flat fee," Dewey said.

Corporate legal departments may have also developed significant portions of their infrastructure around dealing with the billable hour. Moynihan referred to clients building up "micromanagement models" that include investments such as bill review machines and the application of artificial intelligence to measure savings.

"There are people in corporate legal departments who are quite proud of all that they've built that delivers savings or perceived savings by measuring the billable hour and controlling rate increases. So they too, just like law firms, have this infrastructure that the are kind of proud of," Moynihan said.

Of course, some corporate clients are eager to pursue alternate law firm fee arrangements—they just don't know how to make it happen. Burney pointed out that attorneys are trained to argue for a living, so clients attempting to guide their representation away from the billable hour model may already be at a disadvantage. Even threats of jumping ship to another firm or legal service provider aren't always cost effective.

However, tech may not entirely be down for the count in the bout against the billable hour. Matter management and billing tools, for instance, can help clients keep track of how many attorney hours are being expended on a certain task and at what price point. "That's how most corporate clients can come back [to firms] and say, 'Wait a minute, we now see how the sausage is made and all of the ridiculous time that is spent on things that don't need a lot of time spent on them,'" Burney said.

If tech does eventually defeat the billable hour, it may be with an assist from alternative legal service providers (ALSPs). Moynihan pointed out that the amount of competition firms face from ALSP's or even the Big Four is rising and with technology making it easier than ever for clients to bid out projects, law firms may have to reevaluate their long-term survival against the short-term gains of the billable hour.

"They will reach a tipping point where that longer-term thinking prevails," Moynihan said.