Night vision when ir is off doesn't meet my expectation, hard to focus - Bushnell 2.5x42mm Night Vision Binoculars

When IR light is off, the night vision doesn't meet my expectation. Because this is my first night vision tool, and it's a first generation, I may expect too much. I have to turn object len one by one to do focus. Why don't let me focus both sides together, as what I can do to focus a regular binocular? other then these two points, I think the product quality is very good. I guess there may have good reasons behind the two points. Can somebody share the reasons?
Pros: integration, water resistent, easy to hold, clip on strap
Cons: night vision when IR is off, the way to do focus

This review was written in the old system and had content requirements that are different than reviews written today.