This is bad, bad news for MSNBC. Typically, when a new high-profile show shows up, people watch for at least the first couple of shows, which causes a ratings spike. Then things settle down, and if it's a hit, people keep watching and the ratings hold steady or rise. If it's a dud, the ratings fall.
If the ratings you have for the first show are lower than the ones before it, people have already written it off.
Take for instance a little TV station up here in Buffalo. It's been several years since this station has been competitive in the ratings, and a fight with unions that has lasted several years, along with serious financial problems and gross mismanagement, pushed the once-vaunted Channel 7 Eyewitness News into a distant third place. Now, channel 7 still has a decent news product (compared to channel 2, a channel bloviating in its own self-importance and channel 4, whose stories are written by the daughter of the local Democratic Party chairman-- I'm not kidding). Yet the new general manager they hired decided to make a big splash: they hired two out-of-town news anchors for a new morning show. They then decided to advertise heavily during a Buffalo Bills game: the problem is, those ads featured the new anchor team mangling every town name in Western New York.
Now, at this time, channel 2 has about a 6 share, channel 4 has about a 5, and channel 7 is hovering a little over a 2 share. The new anchor team got a 1.9 their first day, indeed dropping even with the new ad push. A month later, it had plummeted to a 1 share.
So, yeah, if Baldwin's ratings went down on the first day, that is a bad, bad sign.