There’s a long standing issue with triggers installed programmatically by other triggers, that was kind of fixed last year, but users are still reporting problems, at least in certain locations (Japan, India and others). The issue in short: triggers installed programmatically would not be created, or fail systematically.
In many cases this affects add-ons (and, to be noted, the issue still persists when testing them, see Testing details); I had a slightly different scenario: a webapp that, when executed (doGet), would install a time based trigger for the user executing the script.
This article provides two solutions to an annoying issue and unlocks many possibilities for programmatically installed triggers.
