1
If the opening drags, fix timing first
Find the first useful action or line. Remove the wait before it, then cut the ending after the point has landed. Play the join at normal speed; if it feels abrupt, restore a fraction of a second rather than adding a transition.
2
If the message is confusing, fix sequence next
Put clips in the order a new viewer needs: context, action, result. Remove repeated attempts and check whether each remaining shot answers a question raised by the previous one. Edit video for comprehension before polishing color.
3
If viewers must strain, fix sound and framing
Listen through the phone speaker and headphones. Balance speech against music, check caption timing if you use captions, then preview the frame in its intended shape. Leave room around faces and text before you export.