In the docs section https://docs.camunda.org/manual/latest/user-guide/process-engine/the-job-executor/#failed-jobs, it reads:

a job will be retried a number of times (by default 3)

The word "retried" suggests that the job, by default, will be executed four times in total (the initial execution and three retries) before it's considered as failed.
This is inaccurate since the total number of job executions is three by default.

https://github.com/camunda/camunda-docs-manual/pull/273 fixes that.