Why can't I see a job that ran a while ago?

By default you can see only recent jobs. To see a job that happened longer ago, click the Icon shows a clock and a report. View Full Job History icon.

To change back, click the Icon shows a funnel and a report. View Recent Jobs Only icon.

This applies to the Home page Data Loads tab and the Run History pane of the Transformations and Validation Checks tab.