Exactly because He is infinite, the finite limited forms cannot bear His Power hence it takes long time. Otherwise simply multiplying Himself endlessly is already achieved in the sense that God dwells in every form. A continuous replication of God will not lead to variety and diversity which would mean sameness everywhere. For the creation of diversity God must first conceal Himself and then slowly make His infinity emerge in a unique way through each form. Hence the long process. It is somewhat like preparing different flavours of ice cream rather than the standard kulfi.
Affectionately,
Alok Da
