Yes, there is something missing but for reason, you know in Chinese, four has special meaning, people learned that there are four directions, North, East, South, West, so four means something just fine. in other hands, the pronunciation of four is similar with the pronunciation of death in Chinese, so four is good, but the pronunciation of four is bad, you can take the meaning of four, but avoid to speak it out.
So most famous saying in Chinese has four words, this one missed something just for align.
It should be: 爱 something, 不(愿意)放手
You love something, you don't want it to get out of your hand. You can not say love someone, do not want to let him/her go, only for something.
I bought a new cellphone, and I like it very much, you can say: 刚买的新手机太酷了，简直爱不释手,
small toy, cellphone, art craft, only something that can be held in your hand.