Everyone interprets love in different ways. They say there are 5 languages of love and every person must discover which is required for them to feel loved. https://www.goodnet.org/articles/5-love-languages-which-one-are-you offers a test to demonstrate which qualities they require. For me it's through affection and affirmation. Love also does come in different levels of intensity. For example, I love my friends, I also love my kids more. My kids, I love both of them but I also love them differently. So I don't think that love in itself has a set value or threshold. Love is something subjective and very personal. It is also said that the highest level of love, beyond being in love with somebody is what's called agape love. You can love somebody and not be in love with them but you cannot be in love with somebody but not love them. Affirmation or reassurance of love is something which breeds positivity and many people lack. So that's why psychologists are taught to project that to people. Sadly, many people have never known love and some may never experience it.