aria_read_log -a unnecessary ?!?

I tried a lot to get incremental backups with Aria logs to work. When I succeeded In noticed that aria_read_log -a appears to be unnecessary! Steps:

cd <datadir>
mysql
-> USE demo
-> CREATE TABLE demo (id CHAR(17), c1 TINYINT UNSIGNED, c2 TINYINT UNSIGNED, c3 INT, c4 INT, PRIMARY KEY(id)) ENGINE=aria; exit;
rm aria_log*
systemctl restart mariadb
cp -r * <backup_folder>
mysql
-> USE demo
-> INSERT INTO demo VALUES ('aaaaaaaaaaaaaaaa',0,0,1,1); exit;
cp aria_log* <incremental_folder>
systemctl stop mariadb
cp -r <backup_folder>/* .
cp <incremental_folder>/* .

aria_read_log -a <- this is optional

systemctl start mariadb
mysql
-> USE demo
-> SELECT * FROM demo;

Result is the inserted line from the incremental backup. I don't need aria_read_log -a !!!

Perhaps it doesn't work without aria_read_log if the logs get bigger or mutliple file?

Perhaps I'm using aria_read_log -a wrong and it could have suceeded skipping a lot of my steps, using it another way. But how, if so?