This is a reasonable summary that roughly answers your question. https://www.forbes.com/sites/gabrielshaoolian/2017/02/07/logo-redesign-what-to-consider-when-i

This is a reasonable summary that roughly answers your question. https://www.forbes.com/sites/gabrielshaoolian/2017/02/07/logo-redesign-what-to-consider-when-its-time-for-a-brand-update/ https://www.forbes.com/sites/gabrielshaoolian/2017/02/07/log... tldr; when your designers tell you it’s out of date with current design trends and that they can evoke a better brand response with a new design.