Good points raised above.

In answer to your question a logline isn’t suppose to explain all the plot points of the inner journey, as DPG mentioned it’s the outer journey plot that it’s suppose to tell. It’s through the character and obstacle descriptions that the inner journey is inferred, and it’s through the cause and effect relationship between the inciting incident and goal that the motivations and stakes are made clear.

For example:

The inciting incident of the galactic empire burning Luke’s uncle and aunt motivated him to seek revenge against the man in charge. It’s also connected via a cause and effect relationship to his outer journey goal – stopping the empire’s Death Star.? However, a peek under the surface and we can see that the hero needs to learn to let go of anger on account of being vengeful – his inner journey goal.

If we keep looking we see that the empire is dangerous and well equipped (killed and burned a whole settlement in? a few hours), so now we also get a sense of the magnitude of the hero’s obstacle.

But wait there’s more!!!

As this is a galactic empire the reader now knows the stakes at hand – freedom across the whole galaxy.

So much was inferred with so few words, point is that with a well structured logline a strong concept will answer all the required questions.