Elisabeth's example is a good one. We often rely on favourite fall-back outfits (FFBO) and that's not a bad thing -- it's great to know that certain combinations will reliably work for us. They may or may not make us happiest.
Some of this will depend on personality and style goals.
Someone who feels happiest in old favourites will likely find her happiness factor is highest when she wears items that have been in her closet a while, or in the same silhouette as other favourites, or perhaps when she includes some sentimental pieces.
Someone who enjoys trying new trends will probably feel happier in something new, whether or not it is a familiar style.
Style persona is also relevant. Angie has mentioned that her happiness factor is highest when she combines classics with modern on trend pieces. Someone else might feel uncomfortable in trendy pieces. Yet another person would hate to wear any classic pieces at all.
Some members here have come up with personal "rubrics" which make outfits feel most like them, and raise their happiness levels. So, for example: someone might try to include a bit of structure, some retro elements, colour, and something rugged, to ensure a higher happiness quotient.
Comfort is an important component of happiness -- and for some, it is probably more important than for others. Also, there are different aspects to comfort. For some, it's about matching an environmental norm and fitting in. For others, it's about fabric texture. For still others, it's about fit, or disguising perceived figure flaws. But I tend to agree with those who say that dressing to hide one's "flaws" will be unlikely to lead to happiness. Celebrating what's wonderful is far more likely to help a person develop her true style.
