I was at los angeles airport and I wanted to get some good ole in-n-out burger. I checked the prices for uber and lyft and it was around $15 to get there - no two mention coming back to the airport. Almost $30 to get a burger. Worst part was that in-n-out was maybe 5 miles away from there. I thought to myself "man, I wish I had a friend who could pick me up and take me there, and I could just give them a ride some other time" - and boom. The seed was planted. Finalized and polished the idea for the rest of the day.