If you do the same ole same ole workout regime each week, expect to plateau and stop seeing results, the body easily adapts.
Mix it up - trick the body so it doesn't know what's coming next.
When your workout is nolonger a challenge it's time to change it. This is easily done by changing the number of reps, the movement pace, the added weight, by putting in sprints or high intensity intervals, or even trying something new.
If you are looking for results, break out of your comfort zone, feel your exertions again, sweat and, yes, expect to feel sore afterwards.
If you don't create that physical challenge and put the regular effort and focus in to completing your workout, nothing will change!!