Gutters get thought of as a roof accessory, but their real job is foundation protection: moving roof runoff far enough away from your home that it doesn't saturate the soil right against your basement or crawlspace walls.
Soil that repeatedly gets saturated right next to a foundation expands and contracts through wet and dry cycles — and in Michigan, that cycle includes freezing and thawing, which adds pressure as water in the soil freezes and expands. Over time, this contributes to hydrostatic pressure against basement walls, cracks in foundation material, and water intrusion through even small gaps.
An average roof sheds a surprising amount of water during a storm — a 1,500 square foot roof can shed roughly 900+ gallons during a single inch of rainfall. Without gutters, all of that water sheets directly off the roof edge and lands in a narrow band right along your foundation, exactly where you don't want concentrated water.
Watch for erosion channels or bare soil patches directly under downspouts, water stains or efflorescence (white mineral deposits) on basement walls, a musty smell after rain, and visible pooling near the foundation. If any of these sound familiar, start with an inspection of your downspouts and overall gutter condition before assuming the fix has to involve the foundation itself.