If you're on DPPt, you may be very very close to your calibrated delay as well. The closer you are to your calibrated, the more often you can miss it if the delay swings higher momentarily. Delays aren't always stable. So if you calibrated 580, for example, and the delay swings to 598 on a particular soft reset, there's no way you can hit your wanted delay of 594 on that attempt. You have to try again and hope that the next soft reset will have a starting delay below 594.
If I recall correctly, my delays in Platinum were very close to 592. Since I'm using Pikatimer, I never take seeds with delays below 600 anymore. When I was using the computer clock, I tried to keep my delays as close as possible, but I think I may have missed my seed many times due to the delays jumping in the game.