I'm running MacOS 13.2 on a mid-2014 MBP (11,3). I have a 2 TB external HD (Seagate Slim, spinning disk, GUID format) that was partitioned into two 1-TB volumes. Recently, using my main volume's Disk Utility, I deleted one volume and expanded the other to 2 TB. This action corrupted the drive: (1) while the partition map said the volume was 2 TB, Finder's info. window said its size was unchanged, at 1 TB; (2) Disk Utility's sidebar incorrectly depicted the volume as a separate device, rather than a volume on the existing device (it didn't indent it); and (3) First Aid failed.
I thus attempted to erase and reformat the drive. That also failed. I called AppleCare, and the advisor told me I should instead boot into the Recovery volume and try that operation from within its version of Disk Utility. That succeeded, on the first try. The disk is now behaving properly.
1) Why was the version of Disk Utility on the Recovery volume able to succeed where the standard version failed? The AppleCare advisor's confidence in the Recovery volume's version suggests this was not a fluke—i.e., that it's understood the latter is more powerful (and/or that it's somehow able to operate more powerfully from within the Recovery volume).
2) Given that the Recovery volume's version of Disk Utility appears to be superior, is it generally advisable for me to perform any future operations to modify or delete volumes using that version, rather than the one on my main drive?