"guesses wrong about how to perform queries all the time. Experienced MySQL users expect to write a lot of FORCE INDEX clauses." This is most generally a sign

"guesses wrong about how to perform queries all the time. Experienced MySQL users expect to write a lot of FORCE INDEX clauses." This is most generally a sign of bad indexing/query construction. I've seen so many databases with dozens of indexs placed on tables (which only had a requirement for a few) because the developers just didn't grasp how they should be setup - which isn't rocket science.