At certain points in the firings ... depending on WHAT you are firing....... there are materials that require oxygen to be present. If it is not present in sufficient volume... then those reactions do not take place properly. So at the time WHEN those reactions are happening.... you need enough airflow to supply all that is needed. At certain times...... certain fumes / gases are being created... at those times you need to have enough flow to capture all of them and exhaust them.
At other times pretty much nothing is getting generated or is requiring oxygen ..... and at those times... any airflow is only having the function to convectively help with heat transfer. Since electric kilns are mainly radiative transfer devices...... this flow is of minimal use.
A huge percentage of issues that show up in the finish firing (glaze firing) actually are caused by issues happening in the BISQUE firing that are causing them. People just think they are finish firing problems... because they show up then.
The "stink" mentioned is likely sulphur dioxide leaking out of the kiln. Certainly not good for you...... but by the time is it in the seriously lethal range... it will drive you out of the kiln room/studio.
But it can be a "marker" telling you that other things you CAN'T smell are getting out into the room too.
Professor of Ceramics; New Hampshire Insitute of Art
Guest Professor, Wuxi Institute of Arts and Science, Yixing, China
Former President and Past President; Potters Council