The Crossway people are masters of marketing and have never stumbled or missed a trick
When the ESV first came out, it was not a big hit. Then Crossway realized that they needed to find a market for it, and so they asked themselves what group would be most likely to appreciate a literal but readable translation based on the CT. The answer, reformed Christians. Once they realized this, they simply crafted a marketing plan featuring several respected leaders in the reformed community, and the rest is history. The problem with the HCSB is that the market it was aimed for, Southern Baptists, have by and large rejected it, preferring the KJV, NKJV, and NIV, and non-Baptists tend to associate it with Baptists.
Any speculations about why the Southern Baptists rejected the HCSB in favor of the other translations?
With regard to "Southern Baptists rejecting the HCSB," of course it's not an official rejection. From what I can ascertain, all of the official SBC agencies use it in their publications, including B&H Academic books. A lot of people already used the KJV, NKJV, NASB, NIV or whatever and saw no reason to change. The main impetus behind the Southern Baptists acquiring the rights to the HCSB project was that they had been using the NIV in their publications and didn't want to be forced into using a gender neutral translation. I'm not sure that they ever really thought the HCSB would (or could) be the new "standard" the way that Crossway explicitly has with the ESV from the beginning.
Timing is another issue. Since the HCSB was a new translation and not a revision, the full Bible wasn't issued until 2005, I think. By contrast the ESV hit the shelves in 2002, if not 2001. Remember that they bought the rights to the RSV. Thus, especially in the 2001 edition, it was a light revision of the RSV that didn't take nearly as long to develop as most translations would. Some who were looking for a critical text alternative to the NASB and NIV had already switched to the ESV by the time that the HCSB OT was released some 3-4 years after the ESV. There ARE people who read the HCSB as it is usually around #5 or #6 in the rankings now. (The NKJV seems to be slipping at this point. Some who weren't really interested in the Byzantine text had used it as an alternative to the NASB and NIV, preferring the NKJV's superior literary qualities.) But I think they underestimated the ESV. Crossway was not known as a major publisher at that time, really, and I'm sure some doubted that it would be very successful given that fact. The pamphlet on the ESV by the Trinitarian Bible Society says as much. Previously Crossway had published a lot of worldview stuff (most notably Schaeffer's "Complete Works"), some MacArthur books, etc. They had published a good many Calvinistic works but they were not the juggernaut that they are today.
The ESV found its early base among Calvinistic people. Calvinistic people like Packer, Piper, Grudem and others were involved in it from the beginning and promoted it. So that was the initial base, and it coincided with the rise of the "New Calvinism." I first learned of both translations being in development by reading a footnote about them in Grudem and Poythress' "Gender Neutral Bible Controversy." But the ESV audience has expanded beyond that now. Even though we buy a lot of books and Bibles, there aren't enough of us to push it that high. A good many churches and preachers seem to have switched to either the ESV or HCSB after the 1984 NIV went out of print. I know of non-Calvinist Southern Baptist churches that use it, some charismatics use it, etc. Many no doubt like it because it just "sounds like the Bible" but it is also readable, more or less.
Crossway also made very effective use of the internet from the beginning, making the ESV text freely available for a number of software programs (including things like e-Sword) whereas most other modern translations were not freely available. This continues with software like Olive Tree, where the ESV reference edition is free whereas only the HCSB text edition (I think) is available. The numerous textual notes in the HCSB are one reason for using it for reference purposes if nothing else. That being said, the
HCSB Study Bible website is outstanding. From what I can tell, the whole Study Bible is available for free along with a good many other resources. You've got to pay to get access to the ESV Study Bible online and then it doesn't have as many other free resources as the HCSB site. But I'm guessing that a lot of people aren't even aware of that HCSB site.
With regard to the name, I remember reading somewhere that they had initially wanted to just call it the Christian Standard Bible but out of deference to a publisher named Christan Standard or something similar they called it the HCSB instead. Supposedly they were going to start emphasizing CSB but I haven't seen that to this point.