Why didn't Kirk just blow up the doomsday machine by flying the Constellation inside it instead of waiting for Decker to die first?
You have no idea what a plot hole is.
For someone to say this film has no plot holes, that person is just being obstinate, but I can understand someone enjoying it in spite of them.
In
The Doomsday Machine, we have a logical progression of events that both the viewer and the characters are in on. From the battered
Constellation, to Spock's assessment that no conventional attack can hurt the planet killer, to Decker's suicide and finding that the shuttle explosion caused a power drop on the internal mechanism to Kirk taking the
Constellation on a suicide run. We have an A, B, C, D progression, we don't go from finding the battered
Constellation to Kirk ramming it down the planet killer's throat without fleshing out why Kirk is doing what he is doing.
In
Star Trek 2009, we have both Starfleet and Kirk connecting the "lightening storm in space" and "seismic events on Vulcan" for no other reason than they need to be linked for the story to move forward.
A plot hole, or plothole, is a gap or inconsistency in a storyline that goes against the flow of logic established by the story's plot, or constitutes a blatant omission of relevant information regarding the plot.
I would think that the above would constitute a plot hole.