What is the most important stimulus provoking emotions about a product? Why?

I feel three creates stimuli of owning a product:

1.Brand value-Say owning an Apple device not only creates a social element of recognition but also the user have a feel good emotion of owning something Apple. Same applies for other major brands.

2.Usability/value for money: When a game console releases without backward compatibility (like PS3 supporting all PS2 games), the emotion of relief that the product does more than intended and get you more bang for your buck. Now your new PS3 can also be used with all PS2 games creates a strong emotion.

3.Emotional attachment: This is not particularly governed by any logic. For example, a guy wishes to buy a Harley Davidson because his dad had one, or a person wishes to invest in an insurance policy because his family relied upon it, even though better alternatives are available. So this emotion is close to the  Brand value one, but differs because  the emotional attachment does not follow any defined logic. I have observed people using a particular brand of pen just because they use the same brand in their college days and thus, refuse to part with it.