Why are some lyrics' words written in kanji whose usual reading is not how it is sung?


Some song lyrics in the official lyric book that accompanies the CD is sung as
another word. Usually, the way it is sung is given as a furigana on the kanji:

> Written: 君が希望に変わってゆく  
>  ![enter image description here](https://i.stack.imgur.com/wjP7X.png)  
>  (pardon the quality I took it using iPhone)  
>  Sung: きみがゆめにかわってゆく  
>  (ひとりじゃない by DEEN)
>
> Written: 未来を今描こう  
>  Sung: あすをいまえがこう  
>  (Pray by Every Little Thing)

I wonder why write the word "希望" in the first place. Why not just print word
"ゆめ" since you won’t hear the word "きぼう" in the song anyway? Is there a
cultural/artistic reason for it?

**EDIT by Scratch---Cat** : A really significant example in an extremely well-
known song (senbonzakura)

> きっと終幕｛さいご｝は大団円




Writing the lyrics this way allows the artist to convey an extra bit of the
ulterior meaning. To use the first example, where 希望 is sung as ゆめ, we can
assume that ゆめ was chosen because it fit well with the surrounding syllables.
But ゆめ by itself isn't specific: it could be an abstract dream of what one
wants to do or accomplish, or it could be the sort of dream one sees while
asleep. To show that the former is meant, the lyrics sheet has a synonym, 希望.
Reading 未来 as あす is explained the same way: does あす mean the day after
~~tomorrow~~ today, or more figuratively, the time after today? Providing 未来
in the lyrics sheet lets you know the artist means the latter.




Writing the lyrics this way allows the artist to convey an extra bit of the
ulterior meaning. To use the first example, where 希望 is sung as ゆめ, we can
assume that ゆめ was chosen because it fit well with the surrounding syllables.
But ゆめ by itself isn't specific: it could be an abstract dream of what one
wants to do or accomplish, or it could be the sort of dream one sees while
asleep. To show that the former is meant, the lyrics sheet has a synonym, 希望.
Reading 未来 as あす is explained the same way: does あす mean the day after
~~tomorrow~~ today, or more figuratively, the time after today? Providing 未来
in the lyrics sheet lets you know the artist means the latter.

