They are pretty straight forward in my experience.

The chair of the zoning board will typically read the zoning ordinance that is potentially affected and then describe how it is going to be impacted.

The property owner or their representative is then given time to speak , and the abutters and zoning board members then ask questions.

I’m not sure how it is in other towns, but in mine, the board can make their decision with or without approval of the abutters. But, if you ask serious questions and raise real concerns, then the board members will hopefully be more likely to question the need for the variance.