Issue is when information is edited in JIRA and two people may be working on two separate sub tasks but both edit something on the main issue, there is no notification or lock. Example scenario below.
Scenario
1) User A works on coding subtask 1 and edits a section that is only on the main issue (ie Developer Notes)
2) User B works on a testing subtask and while user A is editing the Developer Notes user B also edits the Developer Notes
3) User A files their edits
4) User B files their edits
5) Everything user A did is overwritten with what user B did and there is nothing to alert user B that user A was working on the issue