Macroscopic　magnetic　properties　of　magnets　strongly　depend　on　the　magnetization　process　and　the　microstructure　of　the　magnets.　Complex　materials　such　as　hard-soft　exchange-coupled　magnets　or　just　real　technical　materials　with　impurities　and　inhomogeneities　exhibit　complex　magnetization　behavior.　Here　we　investigate　the　effects　of　size,　volume　fraction,　and　surroundings　of　inhomogeneities　on　the　magnetic　properties　of　an　inhomogeneous　magnetic　material　via　micromagnetic　simulations.　The　underlying　magnetization　reversal　and　coercivity　mechanisms　are　revealed.　Three　different　demagnetization　characteristics　corresponding　to　the　exchange　coupling　phase,　semi-coupled　phase,　and　decoupled　phase　are　found,　depending　on　the　size　of　inhomogeneities.　In　addition,　the　increase　in　the　size　of　inhomogeneities　leads　to　a　transition　of　the　coercivity　mechanism　from　nucleation　to　pinning.　This　work　could　be　useful　for　optimizing　the　magnetic　properties　of　both　exchange-coupled　nanomagnets　and　inhomogeneous　single-phase　magnets.