A lot of people give smoothies a short blend at full power, but that doesn’t give the best results. Starting at low speed and gradually increasing power lets the blades work better, breaking ingredients down evenly and at the same time. You’re looking for thickened liquid, but not “stand a spoon in it” thick. If the mixture is too thick, add a splash of water or milk to thin out the consistency. If it’s too thin, add a little more frozen fruit.