Gives you the chance to improve your concentration: When you choose to be alone on purpose, you can improve your mindfulness - which is the psychological concept in focusing on your attention and awareness. Since you are free from the distractions of daily life; you can focus your full attention on studying your environment and absorbing the present moment.
It could reduce Depression : Going on a holiday and enjoying some sole time are both potential remedies to reduce/cure mild forms of depression.
You can make new connections: When you travel alone, you are in charge of how you feel. You can choose to be at the popular club where you can meet new people, or you can choose to go on a solo trip. Travelling alone can be a good way to interact with the locals or meet new people, because you don't have anyone to distract you.
Relax as much as you want : Since you are by yourself and don't have a companion whose needs have to be taken care of; you can relax as much you want. You are on your own schedule; therefore you don't have to follow anyone else's. You can afford to take it slow for a few days and plan your journey according to your mood.
Gives you time for reflection : Getting to know the real you is a powerful result of a solo journey. It can be likened to writing a journal. When you travel alone, you face situations you haven't encountered before. How you react to these situations can help you gain a deeper understanding of yourself.