Dangerous and bad? Because you cause breaking of one's Will and if you are not experienced it has pretty big chances for you to get trapped in the spell such You falling deeply in love with the one you just cast a spell..or worse..he/she fall in love so badly with you so he/she can become psychotic-possessive... Anyway there are lots of possibilities that might happen..
In practice, magic has no color since its neutral and you chose for what cause it is used....and if you consider the black magic bad..than ...Is it bad for you to FORCE someone to love you/? Hm?
and about your fails...all i can say is -practice, practice and practice hard ;)
I don't know if black magic is bad or good to say but in what I observed most black magic spells don't strike me as good, but that is strictly my opinion. I don't oppose others using it as I'm sure at one point I will try it at one point.
hmmm but that is a good point. Thank you for your opinions :)
Sorry, I didn't mean to be abrasive with my answer. Generally the trick with love spells is that no matter how much we wish to see all possible ends to the outcome of our magic it is impossible to anticipate all things. Generally, this is also why I find many experienced practitioners stop working heavily in spells seeking to improve the lots of themselves or others and stick to the basics.