Does my calorie deficit have to be consistent?

[chandrest]

So I'm trying to have a calorie deficit but I'm also trying to get used to much smaller portions. I eat slower and stop eating once I'm not hungry anymore because of it but I've noticed that it leads to me having a larger deficit on some days than on others. Will there be a type of yoyo effect if a few days I am within a calorie deficit of 600 kcal and others only 300kcal or am I fine as long as I have a calorie deficit? Thanks in advance for answering my stupid question!