I'm not a CPA, so all I can say is They are trying to simplify how credit losses are accounted for.  Topic 326 plays in this change.  For more reading on Topic 326, here's a link: https://www.cpeonline.com/selfstudycourse/webcast/financial-instruments%3A-credit-losses-%28asc-topic-326%29-%2526-current-expected-credit-loss-%28cecl%29-model-self-study-webinar-%2810-hours%29