This is why you want to run a multiple of 24: (96Hz or 120Hz in our case):
The “2:3 pulldown” telecine process creates a slight error in the video signal compared to the original film frames that can be seen in the above image. This is one reason why films viewed on typical NTSC home equipment may not appear as smooth as when viewed in a cinema and PAL home equipments. The phenomenon is particularly apparent during slow, steady camera movements which appear slightly jerky when telecined. This process is commonly referred to as telecine judder. Reversing the 2-3 pulldown telecine is discussed below.
PAL material in which 2:3 pulldown has been applied, suffers from a similar lack of smoothness, though this effect is not usually called “telecine judder”. Effectively, every 12th film frame is displayed for the duration of three PAL fields (60 milliseconds), whereas the other 11 frames are each displayed for the duration of two PAL fields (40 milliseconds). This causes a slight “hiccup” in the video about twice a second. It is increasingly being referred to as Euro pulldown as it largely affects European territories.
If you don't then this happens ^^^^^^^^^^
And you really don't want judder. It's annoying as ****.
And nearly every movie, series and youtube video is 24p.