It's funny, I asked the same thing myself when i played Battlezone recently where "baseless" missions sadly make up a huge part of the campaign.
I loved these kinds of levels as a kid in games like Command & Conquer and Warcraft II because they were comparably easy to grasp, the management aspect was the hard part for me back then. I would often actually load my brother's saved games at random until I found one of these missions and then only do that one.
In retrospect I'm not a big fan of these kinds of missions. I mean, big surprise, a game usually does not get better by removing one of the core features. These missions are often frustrating and even when they are good, they are usually very shallow and/or suffer from pacing issues. In some titles they are used well as teaching tools, forcing you to learn micro management or specific options that are easily underestimated, but as far as I'm concerned more than 90% of these kinds of missions are unnecessary and even when they are good, they usually aren't as good as the base building missions. Most of the time I just want to get this over with.
And a huge problem with these kinds of missions is, in my experience, that developers tend to use them for stuff that the game just isn't good at, like stealth gameplay and shit. And often enough they are the opposite of teaching tools because they happen to use custom mechanics that do not apply to any other mission.
That said, I guess the StarCraft series uses these missions rather well and they keep the games from getting too monotonous. Some of them were just infuriatingly boring, though.
Post edited September 01, 2018 by F4LL0UT