You don't always have the power to change things. Change the things when you can, yeah, but if you are stuck in traffic, in a boring meeting, in a job you can't quit now, then maybe meditation is a good idea. You can at least not hate your life while you find alternatives.

I mean, I find specially hard to improve myself at my job if I hate it, and so it will be harder for me to find somewhere else better. If I'm mindful, I will actually keep working hard, learning, and I will separate myself from the bad feelings. That doesn't mean I will stop searching for alternatives.