A vendor in Newark taught me more about scheduling than any software

Last spring I was waiting on a pallet jack repair and this old guy from the parts shop started chatting while he swapped the hydraulic hose. He asked how I run my moving crews and I told him we just book jobs back to back, figuring we'd make it up on speed. He laughed and said "your trucks are only making money when they're rolling, but your guys are only making money when they're not exhausted." That hit me because I'd been pushing two crews into 14 hour days for three weeks straight. I started leaving a 45 minute buffer between every single move and cutting jobs that were more than 40 miles apart on the same day. Our on time rate went from like 68% to 91% in a month and the crew quit quitting. Has anyone else had a random stranger or supplier fix a core ops problem with one dumb sentence?