why does ott review is different from the theatrical review ?

if this looks like a copy pasta and an annoying topic i am asking, i apologize in advance. i am not sure what to search in search box.

i have seen this phenomenon for a long time. i saw this for bloody beggar, meiazahgan, now for kaadhalika neram ilai.

imo even i saw in ott. cuz i had exams then.

bloody beggar was kinda funny, loved it.

meiazhagan was good too.

and kaadhalika neramillai i wont watch it cuz i dont like romance movies.

but why do people give good reviews when the movie is out in theatre and wait till ott ?