I suggest you look for the debug log Howto troubleshoot issues with the easy-installer and look for the point where Recovery is uploaded, and whether you get you get a definite success report at that point.
You might search for “waiting for recovery” in the log. Success or fail should be recorded fairly near to this section of the log.
Another common cause of this situation is described here Know your hardware - Samsung #Your first boot into TWRP
Feel free to share the debug log here if you like.
Good luck