Delta Air Lines chief executive officer Ed Bastian recently explained why there’s still a fee for WiFi on Delta flights: Too many users would access the service.

Bastian said if Delta offered free WiFi on flights, too many passengers would access it and overload the system. By charging for the system, Delta ensures only a few users access it as not all passengers are willing to pay for WiFi.

“One of the reasons why I say it’s ‘not a good reason’ why we charge for internet’ — you don’t pay for internet practically anywhere else — is that the planes do not have the technical capacity, and capability yet that if we made it free the system would crash,” Bastian said. “So, once it gets above about a 10% take-rate onboard performance starts to erode…if you turned it on free.”

Bastian did not say why current technology can’t be installed to allow for a couple hundred passengers to access WiFi at the same time without overloading the service.

But, he said there’s hope for improvement in the future. “I’m a firm believer that we need to make Wi-Fi free across all of our service and we are working towards that,” Bastian said.