An ending the reader can predict right away
An ending that leaves major plot points unresolved, introduces a deus ex machina resolution, or contradicts the established themes of the story would likely disappoint a reader. An ambiguous or abrupt ending that doesn't provide closure or a sense of fulfillment can also be disappointing to readers.
An ending the reader can predict from the beginning
Readers will probably be disappointed to learn that everything that they had just read had not actually happened, and was just a dream.
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The most likely feeling that a reader would get from an essay without a conclusion is annoyance.
I don't want to disappoint you.She thought she would disappoint her friend.Though she did not wish to disappoint, the flu stopped her from hosting the party.
It would be frustrating to a reader. (apex)
A reader is likely to feel unsatisfied and incomplete when reading an essay without a conclusion. The lack of closure can leave them feeling confused or disconnected from the overall message of the essay.
Yes
can the writer be trusted
To build the readers anticipation about the future
People that are close to you will always have high expectations regarding your life in general. If therefore you fail in your examinations, you will disappoint them as they would love to see you succeed.
The prefix you would use for "appoint" is "re-."
"It is a disappointment that you ask such a thing" You have answered your own question by the question that you wrote. Well done!
A fairy tale ending, in which people receive what they want