You remember the Willems 400-40-4 rule (the “444 rule”)? If not, check under “ARTICLES” above. Part of that rule: indoors, aim the flash 45 degrees behind you.
Of course the main reason is that this way, the light will come from 45 degrees above, well ahead of the subject, rather than from “right above their head” – i.e. the angle of light onto your close-by subjects is good.
But the other reason is also worth mentioning – I am unsure I have pointed that out explicitly. Namely…. If you aim your flash forward, some light will go forward directly to your subject. And what does that do? Cast a shadow: the bane of flash photos. That’s something to watch for very carefully, especially when there is a wall, say, behind your subject.