Does the number of games that a player is involved in reduce the quality of their posts?

I only have a single game so it is not enough of a sample size to judge but I know that one player is only in my game and another is in multiple.
The player in multiple seems to snap off a quick post based on the most current posts without looking back at the previous history.
This is clear from the obvious "mis-plays" that would not happen if they review the history.

Is this a common symptom or just a player's style, no matter the game, do you think?

In reply to GreenTongue (msg # 1):

It might contribute, but not as much as say, a player with a busy life away from the screen vs. one who has time to sit at the computer all day.

I rather expect that personality is more a factor than number of games, and that Rosston has a good point when he posits busy/stressful RL as a larger factor as well.

I agree with the two previous posters. I play in a number of games, but I do take time to craft my responses especially in games that involve deep role-playing (or where your words and tone matter like in a V:tM game).

It can.  I've been in situations where I had six or eight games all active at the same time, and a limited time slot in which to participate.  And on days where I needed to respond to all the games, I definitely felt hurried and wrote more abbreviated versions of posts than I would have otherwise done.  It wasn't always a problem...sometimes I had plenty of time, could sit down and figure out my posts...it was actually relatively rare that I needed to respond in all the games at the same time...and sometimes, a shorter post was actually the most fitting thing to post at the time.  And if there are only three other players in a game, and all the posts are in the same thread, it's less of an issue than if you've got eight or nine active players and posts are scattered across four or five threads...or if each player has only posted once, versus two or three players having an extended conversation that needs to be read before a response is posted.

But, yes, it can impact the quality of the posts.  How much of an impact is impossible to say, however, and if it's a player who's creating really good content, nobody may notice the difference without some serious analysis.  As mentioned above, actual available time to post will have a greater impact...but if you've only got an hour of free time, splitting it four ways versus splitting it eight ways is a significant difference in the amount of time available for each post, especially when you factor in time lost in reading other posted material to catch up to where they need to be.

I think it depends on the person. Certainly, having more games will reduce the amount of time you can devote to each one, but I think each person limits themselves to the number of games they can handle. A person who only has the time to play in one game might be more stressed with that one game than a person who has time for six and is 'only' playing in five.

In my experience it's more a matter of 'immersion'. Some players can immerse themselves in the game reality and can recall what happened to their characters yesterday as easily as they can recall what happened to themselves yesterday. Others just don't seem to recall events or conversations relating to their characters no matter what they do.

Beyond what has been mentioned in terms of time a person has to budget towards a game , which I think is the most valid criteria, a word should probably also be said about "quality".

Mainly that what might be considered "quality" in one game wouldn't pass muster in another.  I've seen games that through various factors encourage each post to be multiple paragraphs of written prose, and others that expressly forbid such micro novellas.

Again, it generally comes down to time and the amount one has to spend, but obviously the more temporally frugal will be able to juggle more of the latter type of game than the former.