Why is it so hard to get an agent's attention?

Why is it so hard to get an agent to even read my work?  And what can be done about it?

The other week I passed on three chapters of a novel, not because I didn't like them, but because I simply didn't have the time to read them. They had been sent to me by an author I'd considered in the past and who I remembered as talented. However, after requesting them, I realized I was simply overwhelmed with work--authors under contract who were ramping up their book publication, clients whose novels I had to read and edit etc. (Not to mention I was moving and had a sinus infection--yes, one's personal life does come into play.)  I could and possibly should have waited until I had more time, but in that moment, simply crossing something off the list was a means to my own sanity, and I very honestly told the writer that after looking at my work load, I didn't have the time to give it the attention it deserved.  She wrote me back the following:

"Thank you for your quick response and for your candor.  While I entirely understand how busy you must be and how that affects your decisions, it's a source of constant frustration to many of the good writers I know that so many agents are in your position.  It means there's a real bottleneck when it comes to having work seriously considered, and I think that's a main driving force behind so many people looking to alternative publishing routes.  At some point, I think this may work out for everyone, but at the moment it's chaotic, confusing and, in some instances, flat out discouraging.  Writers can't get work out there unless they're established and sometimes not even then.  The biggest loser in all this is readers who miss the opportunity to find a broader range of significant voices, which basically means the whole society."

She has a point.  What's a writer to do? This question has stayed with me and I think I have, if not the answer, one suggestion. * I am too busy right now, and I while I have pockets where I am not, for the most part, I am not taking on a lot of new clients.  But, not so long ago I did have the time and I would have jumped at the chance to consider this author's work. In 2002, I was working as a junior agent at an established agency, where I was supported by wonderful, seasoned agents, who not only gave me the chance to take on my own clients, but supported me every step of the way, making introductions to the right editors, offering second reads, and generally encouraging my list. So, my answer to writers who are feeling this bottleneck effect is to cast a wider net when submitting to agents.  A lot of the authors I work with now signed with me when I had three sales under my belt, and they are still with me, working on their 3 or 4th book (a special shout out to Lynne Griffin and Allison Winn Scotch who both chose lil old me over more established agents when I was working at Kneerim & Williams.) So, taking into consideration my own experience as an agent just starting out, I would read the Who We Are sections on agency websites and start submitting to younger agents at those shops. When you get a bite, don't be shy if you have reservations about their small list of sales about asking how the agency works. Is it collegial?  Do they have mentors, etc?

Anyone out there have a similar experience?  Or other advice for writers frustrated with this whole process?

* I have to give credit where credit is due. I sat on an agent panel with the lovely Zoe Pagnamenta, who originally offered this suggestion up when a frustrated author asked her a similar question.