It isn’t “repeating the password,” it is “spamming cout with the currently used password.” (possibly as a silly way of telling you the program has not frozen up).

This uses a bruteforce attack that tests a single password and checks the resultant extraction against the stored CRC; hence it must extract the entire file over and over until a CRC match is found.

Of course, multiple CRC Matches might exist (even if only one is the “full valid file”.)

Now, when you read about 1000 tests per minute… that is either not real-world… or a person who is a moron.

Since this is a glorified batch program, it really only checks to see if an error occurs in extraction.

Another error could be type mismatch or a corrupt archive:
(These throw an error, but the software only checks if an error was thrown; not the type)

You could also be testing against unrealistic scenarios:
Included test files are extremely small. Heavy compression can also slow down decompression. The type of encryption also plays a role in speed of decompression.

Could it be faster still though? Quite likely… but it is what it is.