title: Why are there no best cases in Big O notation for Array/Stack/Queue and other data structures?
body: <p>I was going through this cheat sheet <a href="https://www.packtpub.com/sites/default/files/downloads/4874OS_Appendix_Big_O_Cheat_Sheet.pdf" rel="nofollow noreferrer">https://www.packtpub.com/sites/default/files/downloads/4874OS_Appendix_Big_O_Cheat_Sheet.pdf</a> and I am wondering why there are no best cases mentioned on the website. Why only average and worst cases ? </p>