1) I began to develop a concern that most versions contain more commentary and interpretationthan most readers (and I) realized. The more I studied the original languages, the more frustation I had at some of the popular versions today. I wanted a translation that was as accurate as possible in interpreting the original texts, and was at the same time, readable. I once predominantly used the NIV on Sunday AM (due largely to its popularity and common usage) and the NASB on Wednesday nights (due to its literal accuracy). I think the ESV provides the readability of the NIV without the over-simplicity and interpretive bent, while improving the flow and readability without sacrificing the literal accuracy of the NASB.
2) I began to be convicted about the popular trend (inspired by Rick Warren, Purpose-Driven style preaching and preachers) of using a disconnected mix of translations and paraphrases in every message instead of utilizing one worthy text. The purpose of picking and choosing a mix of versions seems to be to get the Bible to say what you want it to say by finding certain phrases, words, ideas that may not be well-founded in the original texts, rather than doing the hard work of determining what the Bible actually said (to it's original audience), says (in its proper context), and says today to us (the timeless principles).
3) I have great respect for the team that developed this version and for the Christian leaders, professors, and pastors who endorse it. It was the endorsement of men that I admire that first led me to consider the ESV as my primary text.
While I still utilize a variety of references in personal study, message preparation, devotional reading, and in writing, I rely on the ESV as my primary preaching/teaching text.
These videos will give you more insight as to why: