@psnzMany authors provide their readers with a Profile and/or Blog. The authors often leave behind clues as to what might have happened to them in one or both documents. The status assigned to inactive authors is base on what is known about their status.
In the case of hammingbyrd7, there is no Profile or Blog associated with the author account. There was also a seven year gap between posting Liar's Lair (2008) and Magical Summer (2015). I would say the length of the gap indicates hammingbyrd7 lost interest in writing, but the drive to create reoccurs on occasion.
So far there have been two instances of Inactive Contributors resurfacing after their Contributor Page was developed. So it is possible that there will be another hammingbyrd7 story posted in the future.