I remember having found this in a codebase I inherited.
There was an an unindexed query on a join of three large tables which would generate a resultset of hundred rows. But thanks to our A/B testing setup - only about 40% of users would be shown the resultset - the person who setup the test took the most convenient route and added an if condition in the view. Job done. The query would of course be executed for all users.
The people who were being shown the resultset, were being shown only 5 entries of those hundred. Rest was hidden - by css - on the client side. At some point there used to be a "See More" button to expand the list, but later that button was changed to direct users to different page where a more detailed list was shown.
Moral: Adopting the path of minimal change is a dangerous policy.