There is another point I wish to add to my comment above. At every juncture in life, we are beset with the challenges of milchemes hayetzer. We always have within us the voice guiding us to follow the Will of Hashem and the corresponding Yetzer Horah that cajoles us to folow the negative direction. What I believe happens is that the admonishments that are intended to frighten us away from sinning actually energize the Yetzer Horah. If we handle the positive side well, then we strengthen it enough to overcome the Yetzer Horah. But that task becomes more difficult if we have just fueled the Yetzer Horah with the “fire and brimstone” messages, which is exactly what he wants to hear.
This explanation is suggested numerous times in the seforim of R’ Klonymos Kalman of Piesceznye. This is why he states his position so many times about concentrating on the Yemin Mekareves, as opposed to the weaker Smohl Docheh.