Why don't my horses love each other?

I've recently started farming horses, and according to all the guides I've read, feeding a golden carrot to a horse causes it to enter "love mode" (hearts appear around it) which will then cause it to mate with other nearby horses in "love mode".

I currently have about 10 horses, however when I feed golden carrots to them the majority of the time the carrots just disappear and there is no noticeable change in the horses. Out of the 10 horses, usually only two of them enter "love mode".

Is there a way to increase my success when breeding horses?

Solution 1:

To make horses enter love mode, you either give them a golden carrot or a golden apple, but since golden carrots are a lot cheaper, i'd use those. However, not every horse can enter love mode, only tamed ones. To wild ones it will only increase the success of being tamed --> Horse Wiki for full understanding.

An StackExchange Answer about breeding cooldown if you have questions about that. Basically, 5 min cooldown before parents can breed again.