The reason this is done,is if kodi is closing or your device/kodi is behaving strangely it could be you are low on memory

1.~ From the device home screen click SETTINGS>on the 2nd line(PREFERENCES) scroll along and click MORE SETTINGS

2.~ Click STORAGE & USB take a note of USED STORAGE

3.~ Go back one screen and click APPS>scroll down to Kodi and take a note of Kodi file size

If you found that kodi file size is too big,or your memory is low or are unsure,then let us know the details and we will help you