I created a numbered list in InDesign CS6. The left indent is 0.1875 in and the first line indent is -0.875, so that all of the lines are aligned.
The numbered list looks fine until I reach 10. For 10, 11, 12, etc, the first line is indented an extra .25 in, but all the other lines are still indented 0.1875 in. The numbered list looks something like this:
Ok, so after reading the current responses I was still confused. Then I revisited Adobe's help (http://help.adobe.com/en_US/indesign/cs/using/WSa285fff53dea4f86173837 51001ea8cb3f-6da6a.html) and found this snippet of information that helped:
Note: The Left Indent, First Line Indent, and Tab Position settings in the Bullets And Numbering dialog box are paragraph attributes. For that reason, changing these settings in the Paragraph panel also changes bulleted and numbered list formats.
Tab Position: Activates the tab position to create space between the bullet or number and the start of the list item.
My numbered lists were messing up at 10 because I was only paying attention to the Left Indent and First Line Indent instead of also adjusting the Tab Position. To fix the issue, I went to Paragraph Style Options > Bullets and Numbering > Bullet or Number Position and set the following values:
Left Indent: 0.27 in
First Line Indent: -0.27 in
Tab Position: 0.27 in
Increasing the Tab Position moved over my text enough so that the extra digit in 10 would no longer throw in an extra tab.