Have you noticed the "traffic lights" on the Candidates' page?

The green, yellow or red squares in each candidate record show how long the candidate has spent at a specific funnel stage. When it's less than three days, you will see a green light, three to five days — yellow, and after five days, the light turns red, reminding you to get in touch with the applicant.

When a candidate is hired or rejected, the traffic light is no longer shown in the record as a final decision has been made for them.