I can't make review private?

If you want to record your thoughts about titles without making them reviews, I recommend creating a custom list, and writing the "review" in the comments/description section. You can make the entire list Private.

From the help center:

This page provides answers to the most common questions we often hear about regarding lists on IMDb - if your question isn't answered here, head on over to our community platform Sprinklr where another user should be able to help out. ... Read more.

@Tommypezmaster 

Joined Thu, Jul 8, 2021
  
tommypezmaster
IMDb member since April 2006
https://www.imdb.com/user/ur10357384/

https://www.imdb.com/user/ur10357384/reviews - 239 Reviews

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Why write a Review that only you can read ? ?
Just make it a text file and save it on your home computer ? ?
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MartinHafer
Sun Jun 8 2003
https://www.imdb.com/user/ur2467618/

https://www.imdb.com/user/ur2467618/reviews - 26,321 Reviews
  
TheLittleSongbird 
Fri Jan 30 2009
https://www.imdb.com/user/ur20552756/

https://www.imdb.com/user/ur20552756/reviews - 18,893 Reviews
  
bkoganbing 
Sun Jun 15 2003
https://www.imdb.com/user/ur2483625/

https://www.imdb.com/user/ur2483625/reviews - 17,628 Reviews
  
Michael_Elliott
Sat Nov 25 2006
https://www.imdb.com/user/ur13134536/

https://www.imdb.com/user/ur13134536/reviews - 16,430 Reviews
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Leofwine_draca
May 2000
https://www.imdb.com/user/ur0482513/

https://www.imdb.com/user/ur0482513/reviews - 15,700 Reviews

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