Reason is traditional and practical, not a fixed doctrinal rule. In Chairyavandan and some pratikraman rituals, the Logassa Sutra is deliberately recited only up to the portion “Chandesu Nimma layra” (till Chandraprabhu and Neminath) for these reasons:

• Ritual brevity: Chairyavandan is shorter than full pratikraman, so the Logassa portion is shortened to fit the rite.
• Symbolic sufficiency: this partial recitation is seen as conveying reverence to the Arihants without needing the full list.
• Tradition varies: different Jain communities (and sometimes different sects) have slight variations in how much of Logassa is recited during specific ceremonies; some contexts may recite more or all of Logassa.

If you want, I can share the exact verses around that end point or explain how it is used in a specific tradition (Digambar or Shwetambar) with more detail.

You can read more here and here for the Logassa text itself