BRO: the log files aren't the same every time

Hi, everyone,
I’ve been using BRO for a while, and there is a problem that is when i run BRO , the log files are not the same even if i do the same operation. Specifically, I run BRO at first time, I do some operation, and there is a log file let’s say 1.log (because i do the operation, it’s definitely generate this file), but when I then run BRO next time, and also do the same operation, there is no 1.log file. but after a few minutes, when I run it again, the 1.log file comes out! I just don’t understand why, this really confuses me, and I think if there is a cache or something.
Can anybody help me?

Best Regards

It's generally hard to say what could be causing such a problem, are you able to give more details on what you're trying to do? Are you using any custom script that you can share? Or have an associated pcap file? Which Bro version and how are you running it?

- Jon