It all depends on your lifestyle and clumsiness factor I guess (no offense intended to those who have spoken of numerous drops, seriously)...
I've always babied my phones, especially when I began buying in the high end of the market. Had my previous phone for two years and (ironically) never dropped it bad enough to incur any damage til a couple days before the release of the G4 in the parking lot of the VZW store. Made my decision to switch easier lol.
But really, if you know you're just that person that is more prone to dropping your stuff, sure get a case. If you feel confident you can handle your phone more carefully, then you should be okay without. There's no one that can answer the question of should you get a case better than yourself.
Like I said I keep a couple cases and a cheapo leather back on hand to use if the plan of the day warrants it, but otherwise baby my phone.
Posted via the Android Central App on the LG G4
(or the Samsung Galaxy Tab S 10.5...merica)