Cover letters are the hardest things to write.
Twenty-page research papers, extensive literary analyses, blog posts-- they're all cupcakes compared to cover letters.
Somehow, in less than one page, I'm suppose to:
(1) tell you how much I adore your company,
(2) convince you that I have the passion and the skills for the job, and
(3) try not to sound too effusive since that's probably looked down upon, even though I really do love your company and would be so excited to work for you!
Gah. People who can turn out several cover letters per hour should be considered superheroes in my book.
I won't even mention how long it takes me to come up with one...