Just about everyone can benefit from therapy, most are just unwilling because it is expensive and most don't want the stigma of needing to see a therapist.
Most of us have had things in our childhood that have pretty much messed us up for life. Being abandoned, being ignored, given too much attention, strict rules, not strict enough rules.
As adults we express our feelings about these things through a few different emotions: anxiety, anger, depression.
If you notice you're experiencing these emotions for long periods of time several days a week it might be good to talk to somebody. Even if it's just a session or two. They can tell you if there's really something wrong. They also have all these fun questionnaires and tests that tell them different things about you.