yeah you got to learn to predict that over playing; some missions your companion tags along, others bail the instant you get too close to a marker when you weren't even going for that particular quest, just a proximal abandonment issue... it's frustrating.

you can mod this, though. there are various missions.win.bmd out there on nexus for YOSE that let you take a follower on every mission and they'll stay til you dismiss them, even hurt and near death, which is quite a cheat on breakdown, but to be fair, trying to do a besieged on BD20 or something with an about-to-break blunt melee, a crap .22 pistol with 17 ammo, 2 snacks, 2 morphine, and no influence for support... when you get 4 ferals, 3 jugs and a bloater concealed between 2 rampaging hordes on approach, mixed in with the other 67 zeds, I'm all for a little cheating[www.nexusmods.com]. I won't tell. (I'm sure some of the AIO mods do this too.)

If you are on a mission or out doing something and accept a new mission any partner you brought goes home. This means they have to cross the map to your base on foot. If you go on a mission, make sure you drop the buddy at home before you take it on.

Yes a couple of times those dumb partners got killed just because "time to go home" in the middle of nowhere with hordes and screamers around...
I just reached BD 5 and I'm already scared of doing the besieged missions lol. I think it should not be considered cheating having one partner. Especially since I believe the besieged people never get out of the building and I have to do the cleanup around the house (risking ferals and whatnot).
I'll take a look at the mod thanks

Can anybody confirm the follower leaves when the mission implies having another follower, or is it something else?

Missions involving other enclaves, or morale missions, cause them to leave.

Originally posted by qmjs:

Missions involving other enclaves, or morale missions, cause them to leave.

FYI - @qmjs is a voice of authority on all things SoD.

don't forget by that same token though, you can also milk mission NPCs in reverse; have to pick up a group of 3? sure it's a risk to not take them there before you get jacked up, then again, if you're needing to level a freshly rescued hero you're piloting, or have an empty trunk you need to grab resources to fill up, they'll be your backup until you take em where they go, you want to drag them around while you level up skills or loot 10 buildings in a row, they won't complain...

but it only takes a couple spending 100 influence to immediately have them bail, or worse, bail too close to trouble and get themselves ganked, til you wanna install some cheaty mods.

Oh yes I did that just yesterday, 3 people from an enclave and I dragged them around the map, with their rucks on the back fighting with apparently unlimited stamina!

Just don't switch control with a follower because you MC returns home.