This is not so much about sequels, it’s about naming the 2nd “Part II” and the next “Part III”.
Rocky 2 and 3 were pretty good.
I pity the fool.
Yes and we need to take into account that some stories can't be expressed in an hour and 50 minutes. 'Lord of the Rings' series are good examples. Multiple full length major motion pictures were required and still they had to leave half the source material out for time constrains.