Why isn't threads.seq an actual sequence?

Environment:

All sites, Reporting
Oracle B2C Service

Issue:

Threads.seq (thread sequence) does not contain an actual sequence.

      OR:

Threads.seq (thread sequence) contains duplicates.

Resolution:

The threads.seq order may seem counter intuitive at first glace, but is actually a straightforward mystery. It is possible to create multiple private notes, responses, etc. all at once, appending them one after another to an incident before saving the incident. Each entry increases the threads.seq by one. Each time an incident is saved, the count in threads.seq starts over. Therefore, it can be seen that duplicate values are to be expected in many incidents. 

Example: 

Four private notes are added to an incident. They will have threads.seq values of 1,2,3,4. The incident is saved, and those values are written to the database. Next, two more private notes are added to the incident. They will have threads.seq values of 1 & 2. The record is saved, and those values are written to the database. 

In this case, if a report were to be constructed containing threads.seq, there would be a pair of threads with a sequence of 1, a pair with a sequence of 2, and one each of 3 and 4.