Security? Moments instead of hours. Your bags stay with you, and you know everyone on board. There are NO strangers on this flight. Scheduling? Tell us when you want to leave and we'll be waiting. You spend a few minutes at the airport. So, instead of getting where you are going on the same day, you could get there and be back home for dinner.
But the airlines are cheaper.
Yes, they sometimes are. But are we considering the lost time, extra hotels, meals, transportation and time spent away from whatever is most important to you. And, getting the right aircraft for the number of passengers and the mission, can often make travel for a small group, more cost effective than alternate travel options.