How does the crontab queue work?

Question

Task Schedulers

Good afternoon!
Tell me how the cron'a queue works in this situation:

*/1 * * * * curl http://site.ru/index.php?do=parser; /bin/sleep 6; curl http://site.ru/index.php?do=parser; /bin/sleep 6; curl http://site.ru/index.php?do=parser; /bin/sleep 6; curl http://site.ru/index.php?do=parser; /bin/sleep 6; curl http://site.ru/index.php?do=parser; /bin/sleep 6; curl http://site.ru/index.php?do=parser; /bin/sleep 6;  curl http://site.ru/index.php?do=parser; /bin/sleep 6;  curl http://site.ru/index.php?do=parser; /bin/sleep 6;  curl http://site.ru/index.php?do=parser; /bin/sleep 6;  curl http://site.ru/index.php?do=parser

I have 2 options:
1. Every 6 seconds, regardless of whether a response is received from the previous curl, start a new curl request.
2. Every 6 sec. after the curl response has been received, execute a new request.
It's just that in fact, instead of 6 seconds, it comes out 10-12.
Thank you!

Answer 1

every minute (at some second, not necessarily at 00 seconds), a script starts executing that looks like
curl site.ru/index.php?do=parser;
/bin/sleep6;
curl site.ru/index.php?do=parser;
/bin/sleep6;
... (total 10 times)
The commands are executed sequentially, hence the first curl is executed, then sleep for 6 seconds, then the next curl is executed.
Curl is not instantaneous, so there will be 6 seconds between two curls + the execution time of the previous curl.
Apparently, the person who wrote this has no idea about cycles and running processes in the background, the command can be shortened to
for var in {1..10}; do sleep 6; curl site.ru/index.php?do=parser;done