As well as introducing a vast variety of new elements to the series, Persona 5 has also retained one of the key character development mechanics known as Social Stats (Persona 5 Stats). If you have never encountered them before, these vital stats allow you to access particular Confidants, as well as use alternative dialogue options and perform certain tasks that require you to have a bit more life experience. If you have played the previous entry in the series, you will be most familiar with the Social Stats that you need to build up, but there have been a few minor alterations which differentiate it from Persona 4.
Your main character in Persona 5 has five stats, all of which each have five levels of progression known as Ranks, and every activity you undertake will increase them in varying amounts. It is unlikely that you will be able to reach Rank 5 for every Social Stat first time around, but if you do decide to undertake the challenge, be wise on which activities you choose alongside your heists as the Phantom Thieves.