How often does RFE apply to H4 visa?

I am currently on H1B and I got my stamping in Oct 2016 after a month of delay by RFE. I am getting married Nov 2017 and will be applying for H4 for my spouse immediately after marriage. Is there a possibility that her application would also get a RFE or H4 is more straightforward? What are the general grounds for such a thing happening?

Thanks