This summary is not the rule. The rule text controls.
If someone is named to serve as an administrator of an estate but doesn't actually step up and complete the paperwork, this rule gives other people a way to push things forward. A person with a stake in the estate, the public administrator, the county's chief financial officer, or a creditor can ask the court to set a deadline.
Once the court sets that deadline, the named administrator has to qualify by that date. Qualifying means completing the legal steps needed to officially take on the role, like filing the right documents with the court.
If the person misses that deadline, the court treats it as if they gave up the job on their own. This keeps estates from getting stuck in limbo when someone is named to handle the estate but never follows through. The court can then move forward with appointing someone else to take care of it.