Present Perfect or Past simple

May I ask why past simple is preferable here?

Let's imagine My friend has just left home but he forgot to take something I am calling her and saying Go back you forgot or you have forgotten to take important documents

Hi,

I think you could say both, but using the present perfect indicates that it is more recent and/or the action (of you forgetting the documents) has present significance (your friend doesn't have those docum

Sir, Could you please tell me if I'm wrong to say that present perfect is better or more appropriate for the reasons I gave in that case.

Thank you.

LaboriousCould you please tell me if I'm wrong to say that present perfect is better or more appropriate for the reasons I gave in that case.

You have nicely stated the general grammar 'rule', Laborious, but in that situation, I think it just as likely that my suggestion above would be used.

Perfect StrangerMay I ask why past simple is preferable here?

I didn't say it was 'preferable'. Real native speakers shouting out the door with an urgent message to a departing friend are likely to use the quickest and most direct phrases.