My coworker is taking his one-year old son to Disney for the first time and the last time he actually went was like a decade ago. He doesn't get that you need to plan something in advance and you can't just wing it. I'm trying to help him, but he said there's no way to know what they'll be doing with a baby to be able to make fast passes. I don't have kids that little so maybe he's right? But I feel like he should make something, it's not like it will cost him anything if he doesn't use it. How do I convince him to make fast passes? They are going for only three days. I just know he's going to come back and complain the lines were really long and couldn't get anything done. I want him to have a good time.
I totally understand your frustration! My physical therapist went with his family last spring when his daughter's cheer team got into one of those competitions. They are experienced
Disneyland visitors, so understand what Fastpasses are, but didn't realize you can book in advance. He knew I was planning a trip later that year, so we chatted a bit, and I tried to give advice about Fastpasses, ADRs (or just general food places), park hours, transport, etc. They also had a younger kid, so I tried to tell him about rider swap too. He wasn't too interested so I dropped it.
When they got back he explained how wasted he felt that trip was. They ate almost every meal at the All Star food courts

crazy2

, never got a single fastpass, and went on 4 rides. They never even went to Epcot. At Animal Kingdom, they waited for 90 minutes for Kali River Rapids and that was it (didn't even go on the Safari or Everest or anything). At DHS, his fiancee and daughter went on Tower of Terror, while he waited with the younger kid, so he didn't ride. At MK, they went on only a couple rides (including 7DMT with a 2 hr wait). I guess at the end the kids had a fun time being able to run around the resort with a group of kids (I shudder to think about other guests at All Star Sports that week), while the parents were able to spend time with other cheer parents.
After I got back from my trip I explained how I got to eat at so many fun restaurants, go on all the rides, most multiple times, and just have an amazing time. There probably will be future trips with the cheer group, so will at least know for the future. And they also explained they may add a few days on at the end at a nicer resort to be able to enjoy that!
So, I guess the best advice is, to just wait and see. You tried, and he didn't listen, so just let it go, no matter how frustrating it is

! Maybe closer to the trip he will ask other questions, so help him then. Otherwise, just accept they will have to make the most of their trip without planning. Good luck!