How many cards should one lecture become?

The number nobody agrees on

Forum threads put it anywhere from 15 to 170 cards a lecture, and they are all right, because the number depends on the subject. Pharmacology runs dense. Anatomy with figures runs long. A history lecture might be twenty.

The rule that actually works

Decide your review budget first: the number of reviews you can honestly do every day without the queue turning into debt. For most people that is 40 to 80. Then make cards up to the budget, starting with what you would be asked, and stop.

A deck you review every day at 50 cards beats a deck of 200 that you abandon in week four.

The failure that is invisible

Too many cards is a problem you notice. Too few is one you do not. A deck missing a third of the lecture looks exactly like a complete one until the exam.

That is why Lovelydeck lists the slides that produced no card before you add anything. The list names the slide, so you can decide whether it deserved one, and it sets aside the slides that are only a diagram or an agenda so you are not chasing ghosts.

Where to start

Generate from the lecture, look at the coverage list, add the cards that ask what you would be asked, and let the due forecast tell you whether the deck fits your week.