We have never successfully been able to put a finger on this intangible feeling we get. I came upon a possible answer - let me know whether you agree. We find a special feeling within ourselves when we are made to feel that we are needed for the special things that we can do. They respond to your attention, and this interaction of care and its rewarding outcome is a positive behavioural feedback that creates an intimate bonding of interdependence. Their little quaint idiosyncrasies endear them all the more.
Love is that way, but in a stronger, more extreme sense.
We tend to forget and take for granted things that are independent of our attentions and can function without our input, regardless of us. This is why there are few who say that toasters have soul or provide companionship. It also explains why we fall out of love in a relationship, when something else occupies our protracted attentions, and the positive feedback dwindles. Our Life is a measure of passing Time - it surrounds us in its Past, Present and the Future. And so it is with watches.