Before switching to sourdough permanently, I spent about a year using commercial yeast. It works — it is fast, reliable, and produces a perfectly decent loaf. But it does not do what a wild-yeast starter does, and understanding why helps explain everything else about sourdough.

The key difference is not just speed. Commercial yeast is a single standardised strain of Saccharomyces cerevisiae. Wild-yeast cultures are entire ecosystems. The diversity of that ecosystem is where the flavour comes from.

The practical takeaway: if time is the constraint, use commercial yeast. If flavour and fermentation depth are the objective, grow a starter.