Depends on how you quantize, beginning with grid vs. groove and then moving on to other parameters such as your selected quantize value. Also, depending on how far off your original audio happens to be and where you think a transient should be vs. where S1 detects it to be, you may still need to use audio bending to get some transients where you want them. Here are some useful deep dives into quantizing both audio and MIDI in S1.