There’s a book I’m reading where the author is kind of spoiling it for me. (No names, this isn’t about blaming and shaming.) They keep putting in lines like, “If only I had listened, how many people wouldn’t have died?” And I mean, a similar line to this three times in one chapter. The main character is saying it about their own military plans.
As an author, I’m not sure why you would do this. I think they’re trying to be foreboding and create tension around the outcome. For me, this spoils the tension instead. It’s telling us the plan will not go well, even before the character begins. It’s also a first-person narrator, so that character is clearly going to survive whatever happens. I don’t need to worry about them, and I should.
As a reader, I prefer being allowed to wonder. I mean, this character is a rash young man who’s wildly over-promising. You don’t need to tell me the plan will be a disaster. (And if the plan is not a disaster, then I will feel lied to.)
Anyway, as a writer with decades of experience, I would just urge my fellow writers not to do this. There is great power in letting the reader build anticipation for themselves.
Speaking of fellow writers — as a WEA/SEA member, I stand in solidarity with the WGA. Stay strong, union brothers and sisters!
Have you read one of my books? Then it would be great for you to leave a review! Meanwhile, if you’d like to learn more about me and my work, check out my website, Facebook, Instagram and/or CounterSocial.
Wyrmflight 
I would wonder too why an author would do that. Maybe it will lead to an unexpected twist.
I did write a one-act play that was produced where I essentially gave away the ending about half to two thirds through the play. But the audience was still surprised at the ending.
Maybe it isn’t where you end up, but how you get there?
I agree about “how you get there.” As a reader/viewer/listener, we’re typically going to spend a lot more time on the trip than at “The End.” (Of course there are some works where many people found the ending disappointing.)
And there are some famous works that give away the ending in the beginning, such as these three:
J.R.R. Tolkien’s *The Hobbit, or There and Back Again* gives away the ending in the secondary-/sub-title. We know from the title they’re going to get back.
Jules Verne’s *Around the World in Eighty Days* also gives away the ending in the title.
And William Shakespeare’s *Romeo and Juliet* not only gives away the ending but even the main plot in the prologue.
I understand this one. Seems like you’re being told about a pending disaster, but when it happens you did prepare and are not emotional about it.
But, don’t we want our readers to be emotional at the ending?
Exactly. Seems this is throwing water on the fire.