Cracks in the concrete are completely normal as long as they are narrower than 1/4″.
There are multiple factors contribute to the cracks. To name a few: Settling, changes in temperatures, weight pressure fluctuations, changes in humidity, shrinkage and expansion, etc. In addition, while 85% of the curing process occurs within the first 3-4 weeks, full curing process takes more than 6 months, etc. If cracks are 1/4″ or wider, it is a sign of poor concrete mix or reinforcement inside of the concrete. Normally smaller cracks are to be sealed after a year of use. Alternatively, it may be painted or epoxy polyurethane covering may be applied. And in no way, they are affecting the sturdiness of your garage foundation. At Alta Home, we offer placement of control joints at no extra cost upon customer request. This will ensure all those smaller cracks follow the saw cut in the middle of the pad.