That's for plugins with an explicit fixed latency to use PDC. If a plugin doesn't request latency, which most do not, they have the duration of the DAW audio bu

That's for plugins with an explicit fixed latency to use PDC. If a plugin doesn't request latency, which most do not, they have the duration of the DAW audio buffer to complete their processing. If the combined processing of all active plugins on a single thread exceeds the audio buffer duration you get audio drop-outs, or portions of the buffer which are just zeroes because they were unable to be processed in time.