finder
In the image of an OSX Yosemite 10.10.2 Finder window below, you can see that the content of the 'blog' folder has been most recently modified. However, the 'Date modified' sort of the parent folder 'D' is not showing the 'blog' folder at the top of the list.
Why is this, and is there a way to sort the list as I intend? I seem to remember it was fine in previous versions of OSX.
Use the "clean up by" option, not the "arrange by" one.
Finder and the file dialogs have had two different sorting modes (sort by and arrange by) since 10.7. In the first screenshot, the arrange by mode is probably set to date created or date last opened. Try changing it to none instead:
The menu shown above changes the arrange by mode and clicking one of the header columns changes the sort by mode.
Best Answer
Modification dates for folders are only updated when the folder's contents are edited, not the folder's contents' contents. In other words, you probably edited something in the DES folder, which changed the modification date for the DES folder, but you didn't create, remove, or edit anything directly inside the blog folder since 2015-01-06.