Nowadays that we clean for Pesach for weeks before, what do you need to check when you do בדיקת חמץ?
RSZA is quoted in הליכות שלמה פרק ה as saying that nowadays you do not need to go and check every little nook and cranny. What a person needs to do is check every place to make sure that it was cleaned for Pesach, that is the בדיקה. This means that the בדיקה does not need to take all night but rather a short time where you check each room, closet, etc. to make sure that it was cleaned for Pesach.
I heard a similar idea from R' Willig as well that the cleaning that you do before Pesach is מצטרף to your בדיקה and on the night of the 14th you do not need to spend hours checking every spot. All you need to do is make sure that you cleaned everything. The בדיקה is like the final check of all the cleaning that you did.