ndeloof/build-timeout-plugin — comment on commit fb914d593c0dda1962fa3a7e4dbb3e41c941e205
File:  line 0
By ndeloof:

this is a common pattern to include optional plugin code.
As code use FCQN the JVM will never load the associated classes until the if condition is met.

That being said, after discutions about this issue with Kohsuke it seems preferable to refactor the schedule-failed-build to use a RunListerner