The game can’t determine if the reason you left was intentional or unintentional. (Any unintentional reason like crashing or disconnection can be done intentionally)
So yes you will receive leaver penalties if you leave the match for any reason, even those beyond your direct control.
First rule of thumb. If you are experiencing frequent issues that result in leaver penalties being applied. Stop playing ranked until you can address the core issue.
Then if you are crashing or disconnected follow the steps here and then post that specific issue in the forums to allow the community to assist with troubleshooting.