You don’t NEED it but it really depends on what you’re making. I don't use a simple syrup when the cake layers are really thin because the cream between all those layers keeps it moist for longer.u003cbr/u003eFor my fraisier cake (genoise but same rules apply), I did use a simple syrup because the two layers were slightly thicker. If you want to add extra flavor to the cake, a simple syrup is definitely helpful.u003cbr/u003eFor example, the coffee soak in my u003ca href=u0022https://baranbakery.com/recipe-index/u0022u003eu003cstrongu003eTiramisu Cakeu003c/strongu003eu003c/au003e and u003ca href=u0022https://baranbakery.com/french-opera-cake-recipe-double-layers/u0022u003eu003cstrongu003eOpera Cakeu003c/strongu003eu003c/au003e, the simple syrup in my u003ca href=u0022https://baranbakery.com/orange-cranberry-cake/u0022u003eu003cstrongu003eCranberry Orange Cakeu003c/strongu003eu003c/au003e, a lemon simple syrup from my u003ca href=u0022https://baranbakery.com/lemon-poppy-seed-cake/u0022u003eu003cstrongu003eLemon Poppy Seed Cakeu003c/strongu003eu003c/au003e, or just a stronger vanilla flavor.