It usually implies a strong negative connotation. Reticent imparts less of a negative feeling. You could be reluctant to be harsh with another person, whereas you might be reticent about speaking up because you are shy.

Is it good to be reticent?

People who are comfortable expressing their emotions tend to be happier than those who keep their feelings inside. ... Emotional reticence can also contribute to feelings of depression and anxiety, conditions that correlate with life dissatisfaction.

What is a reticent person?

1 : inclined to be silent or uncommunicative in speech : reserved. 2 : restrained in expression, presentation, or appearance the room has an aspect of reticent dignity— A. N. Whitehead. 3 : reluctant.