The large amount of information in the database, combined with suboptimal queries to the database, can slow the load on any site. 5 seconds to load a page in an online store is too long. Even if it has the most useful and sought-after content among its competitors, the site will lose visitors and positions in the search engines.
The growth of the database is a natural result of the expansion of the site. Sometimes, however, the large size of the database may be due to accumulated unnecessary information. Decrease the size of the database is possible by clearing unnecessary information in the tables.
This is a story about a WordPress site having all accelerating and caching technologies activated but still not loading properly just a single product in WooCommerce in rush hours when the product is advertised.