Paradise, really. While I know it isn't a loved episode, thats what people find worst in season two. Shocked.
But no each season usually has a wide range of episodes, some seasons have a very mixed bag. Others have a higher then normal level of quality episodes but all have produced bad episodes.
In my opinion the worst episodes by season for DS9.
1. Move Along Home (Hate it). But I also think these are below average (to worse) episodes (episodes of tv, I would rate a C- or worse). A Man Alone, Babel, Battle Lines, If Wishes Were Horses, Dramatis Personae.
Season Two:Second Sight. I also think thee were below average Melora, Rules of Acquisition, Profit & Loss.
Season Three: Fascination, I also think these are below average: Equilibrium, Meridian (really bad), Life Support (really bad), Heart of Stone (really Bad), Profit Motive, Distant Voices, .
Season Four (my opinion Trek's finest season)The Muse. The only other episode I would rate lower then a C was Body Parts.
Season Five: Ferengi Love Songs, I also found these episodes to be below average: Things Past, Let He Who Is Without Sin... (Really Bad). OVerall a very strong season of Trek (or TV).
Season 6: Profit & Lace. And the following I found to be below average: Sons & daughters, Resurrection, Who Mourns for Morn?, Wrongs Darker then Death or Night, Time's Orphan. But still a strong, season of tv.
Season 7: Extreme Measures. The following I found below average: Chrysalis, Covenant, Prodigal Daughter, and Emperor's New Cloak (really bad).
And DS9 is my favorite Trek.