It is called the airline industry’s number top priority, an absolute necessity that cannot be compromised. It is hyped as being at the heart of the air travel enterprise, a consideration so crucial that it outweighs all others. It is by one account, “the cornerstone of the contract between airlines and their customers.” Safety is a word synonymous with air travel.

According to the International Civil Aviation Organization, it refers to a situation where, “the possibility of harm to persons or of property damage is reduced to, and maintained at or below, an acceptable level through a continuing process of hazard identification and safety risk management.” For most passengers, safety means arriving at their destination in one piece.

Countless programs have been implemented to do just that. Audits aid in identifying potential safety risks, training helps executives better understand how their decision impact the lives of passengers, and financial incentives encourage frontline workers to perform their job more carefully. Safety is treated as a team sport and rightly so.

But it can also be an expensive one. For example, recently announced efforts to strengthen safety management processes in the United States are expected to cost local carriers some $224 million. That figure jumps to over $300 million when it comes to keeping sleepy pilots out of the cockpit. Safety advocates see these costs as investments that help avoid future catastrophe. The reality however, is more complicated.

Limited capital means airlines must wisely choose where to spend their money. When it comes to safety, the investment of choice has historically been technology. After all, picking a more reliable engine means fewer chances of that engine failing in flight. And choosing the right automation means fewer opportunities for human error.

From electronic checklists to collision-avoidance systems to radar displays, the millions spent on safety-related technology mean accidents today are few and far between. It also means that justifying the need to further invest in safety is difficult. Why spend more when probability is on your side. The odds of being killed in a plane crash are one in 11 million. The odds of being killed on the road are one in 5000.

Put another way, the riskiest part of air travel today is the journey to and from the airport. This explains why some safety programs, such as placing stricter limits on working hours, face opposition from airlines. The rarity of accidents almost guarantees that the benefits of these programs will never been realized.

Safety is also not what airlines sell. What is being sold is a promise to get passengers from one city to another. While safety plays a role in delivering that promise, so do factors like punctuality (arriving late is bad), predictability (not knowing when one will arrive is worse), and cost-effectiveness (charging exorbitantly more than your competitors is a surefire way of losing business). And it doesn’t stop there.

Surveys show that airline choice is also influenced by factors such as customer service quality, hassle-free connectivity, cabin seat comfort, wireless access, and the flexibility of frequent flier programs. Airlines have to deliver more than ‘just’ safety because passengers demand more. Not meeting this demand risks losing out to competitors. And since deregulation, there are plenty of them around.

Investing in safety is important. But opposing such investment shouldn’t imply that safety doesn’t matter. It does, but it is not an easy matter.