What are the benefits for big companies to change their logo from time to time?
TOO CHANGE OR NOT TO CHANGE (BRAND), THAT IS THE QUESTION
Very rarely do companies change logos and or brands but sometimes the image/slogan can become outdated, culturally offensive, etc.
There are times when a fresh reboot can give your company/brand new life allowing you to begin afresh marketing campaigns. But this is not something you do every 2 years. In a 20 years period, you may get one bite NEVER more than 2 at this apple. (making a sweeping brand change)