Après la création d’un compte sur un site : connectez moi automatiquement s.v.p.

La même erreur est commise depuis 1995 :

The reason your users create an account is probably because you required them to so in order to do/view/get whatever – so give it to them instantly after they signed up. Don’t require them to sign-in to the account they just created.

Oh, and do you truely need me to activate my account?

12 Ways to Simplify ‘Sign-Up’