:::Raykyogrou0, 
 :::Do you see where I asked "You understand why Hurricane is relevant? " Do you understand why Hurricane is relevant?  
 :::But in answer to your question, in this case for at least 5 reasons: 
 :::(1) Because "Flower Power" and "Flower Power" and "Flower Power"  are ambiguous. Looking at "Flower Power" and "Flower Power" and "Flower Power" it is impossible to tell which is the 1967 English song, which is the 2004 Ibiza instrumental, and which is the 2012 Japanese song beginning "Hikari to yami no mayonaka,..." 
 :::(2) Because the 2004 instrumental is 10x more notable than the 2012 Japanese song in English books 
 :::(3) Because more English speaking people listen to English-language songs than listen to Japanese-language songs (just as on ja.wp Japanese songs get priority), therefore inevitably more English speaking people will be looking for the Ibiza club hit. 
 :::(4) Because our Users don't know that Flower Power is covered in the Danii Minogue article. Readers come to Wikipedia knowing what exists in the real universe, not what we have decided should be forked or merged. 
 :::(5) Because removing (Girls' Generation song) is unhelpful to Girls' Generation fans too.  
 :::These 5 are fairly typical of these kind of WP:DAB issues.