One of the best things I have heard is foreplay doesn't start in the bedroom, it starts in the flirting.
When you first meet someone and have that chemistry, the sexual tension in itself is foreplay.
Sex is just an action, but falling in love includes the foreplay.
Foreplay means you don't want to rush sex, you want to take your time and enjoy every bit of it.
When there is no foreplay there's no desire in wanting to please each other, and that is a major difference between sex and love.