There are many instances that I've attended a meeting. During the first 30 minutes the meeting is very okay, every employees are focused on the meeting, giving ideas and you can really see the brainstorming.
The problem comes when the duration of the meeting stays longer than 30 minutes, the employees will start asking unnecessary questions that are not related to the topic, some of them are boasting about their background, some are just chitchatting. Those things makes the meeting longer, this makes me unproductive.
My question is what should I do? Should I excuse myself?(How?), do I have the authority to do that? Assuming that I'am just a regular employee among the company.