After David established himself in Jerusalem, Nathan prophesied:
“The Lord declares to you that He, the Lord, will establish a house for you. When your days are done and you lie with your fathers, I will raise up your offspring after you, one of your own issue, and I will establish his kingship. He shall build a house for My name, and I will establish his royal throne forever. I will be a father to him, and he shall be a son to Me. When he does wrong, I will chastise him with the rod of men and the affliction of mortals; but I will never withdraw My favor from him as I withdrew it from Saul, whom I removed to make room for you. Your house and your kingship shall ever be secure before you; your throne shall be established forever.”—2nd Samuel 7:11b-16 (NJPS)
Now during David's life, the prophesy was touch and go at times, but Solomon did fulfill all but the last sentence. However, by the end of the book of Kings, it seems difficult to say that David's "throne shall be established forever." Was Nathan a false prophet? Or more charitably, did he or whoever recorded and edited his words embellish them by including the word "forever"?
For clarity, I'm well aware of the Christian interpretation of the prophesy, but for the purposes of this question, I'm more interested in how the compilers of the books of Samuel and Kings viewed Nathan's words.