Uproxx: If you wondered why, at the end of Guardians Of The Galaxy, Baby Groot stopped dancing once Drax the Destroyer looked his way, we now have an answer that amounts to more than, “Because it’s funny, doofus.”
Director James Gunn explained the scene on Doug Benson’s “Doug Loves Movies” podcast.
“There was actually a scene that we cut from the movie where big Groot was dancing to ‘Livin’ Thing’ by ELO. […] And it wasn’t such an elaborate dance. It was more that he was just moving up and down like this, and Drax was dismissive and gave him this look like he was a loser when he did that. […] Dancing is ludicrous to Drax. I don’t think he understands it. If Drax owned a town, if he was a mayor, the first law would be no dancing. But yeah, so at the end of the movie, little baby Groot didn’t want to get caught dancing, because he would kill him.” (transcribed by ComicBook)
Star-Lord needs to teach Drax about a great hero named Ke-vin Ba-con who taught a whole village the virtues of dancing.
Anyway, the earlier dancing scene was cut, but we can see why Gunn kept the last one. He mo-capped himself doing the dancing for that scene, so he could get it just right. Also, how could you delete something this cute?