Manuscripts.  Or more specifically, manuscript submissions.  If there was a bumper sticker for this discussion it could read "So Many Manuscripts, So Little Time."  That's because the number of manuscript submissions that most publishers receive in a year's time is staggering.   

Hint: It's in the thousands.

The number of new authors they publish each year is also staggering.

Hint: You could count them on one hand.

For beginning writers who plan on jumping in the game (i.e. submitting their work to publishers), it is CRITICAL  to learn the rules for prepping a manuscript.  Yes, there are some guidelines.  Yes, you need to learn them and follow them religiously.  No, it's not that hard.  But publishers receive all sorts of submissions from people who don't play by the rules, and those submissions quickly find their way into the circular file.  Understand that publishers are very busy people.  Respect them by submitting your work in the proper format and you'll greatly increase your chances of being taken seriously. 

The first thing is to identity the right publisher for your work (very important step!).  Then visit their website and read their submission guidelines (yes, they tell you...they're very nice that way), keeping in mind that each publisher may have slightly different guidelines.  Most will have you send your work within the body of an email (no attachments), which is quick and cuts down on postage costs.  Saving trees is not a bad thing either.

How they respond is a discussion for another day and would be great material for a Seinfeld episode.  For now, remember that if you want to be taken seriously as a writer you need to take the writing process seriously.   Sounds like a bumper sticker to me.