This chapter begins with the lineage of Jacob through his 12 sons. However, it really focuses upon Judah for most of the chapter.
“Judah heads the tribal genealogies and receives more extensive treatment than any other tribe. The reason for this special prominence is to be found in the central position of David’s line.”
Martin J. Selman
Judah was the Davidic line as well as the lineage of Christ. It would seem the genealogy would focus on these key elements to highlight the success of the Jewish history, however, rebellious and unfaithful names are listed as well
“The sons of Judah: Er, Onan and Shelah; these three Bath-shua the Canaanite bore to him. Now Er, Judah’s firstborn, was evil in the sight of the LORD, and he put him to death. 4 His daughter-in-law Tamar also bore him Perez and Zerah. Judah had five sons in all.”
1 Chronicles 2:3-4 ESV
Along with Er, Achan was also an unfaithful member of the tribe of Judah and was similarly accused of being wicked and unfaithful (Joshua 7). The chronicler also cannot avoid the complex reality of Judah’s daughter-in-law Tamar as well (Genesis 38). All in all, we see both the glory of the Messianic lineage intertwined with the complete depravity of sinful humanity. It is true that no matter what you read in Scripture, the need for a Savior is always prevalent.