After homeowners insurance quotes are accepted by you and you are ready to bind the policy, that quote must go through an insurance underwriting process. The home insurance quotes that the agent presents to you in your initial meeting are generally estimates because they have not been through the underwriting review process.
The underwriting process is for the underwriter to assess the home insurance risk. They assess the exposure to the insurance company from the risk. They assess any liability that may be created from the risk.
In effect, the underwriter assesses whether the home insurance quote is priced to meet any risk, exposure and liability that may arise. If the underwriter feels the homeowners insurance quote is not priced properly, the estimated quote you received can be changed.