These are different methods to run optimization and try to convince the server to clear the cached data and report real status of the tables. Depending on the MySQL/MariaDB configuration, you can often have optimization completed, but the server still reports that it is not optimized due to the cache of the table statistics.
For some servers, different methods offered in this plugin give you better results. According to MySQL documentation ‘OPTIMIZE’ is all you need, but in reallity, it is not that simple.
Regards,
Milan