This is partly psychological, with candle light being associated with intimacy and intimate occasions, whereas fluorescent lights are associated with emotionally cold, impersonal industrial or commercial settings.
Nevertheless, certain physical attributes of the light may also come into play. Candle light is considerably less bright than fluorescent light, as a general thing. People do not willingly read for extended periods of time under candle light. The lights candles put out is also very heavy in the reds, oranges, and yellows, giving the light an emotionally "warm" color. By contrast, fluorescent light of the "cool white" variety usually encountered in office buildings is weak in the red an heavy in the yellow-green part of the spectrum. Fluorescent light also has a line spectrum component that has a subtle (and unappealing) effect on color rendition.
That said, fluorescent light is "softer" than candle light in one sense. A fluorescent light emits over an extended area and is less uncomfortable to look directly into than the small, concentrated candle flame that somewhat resembles a point source of light.