I hear all the time to rack of the lees or bad flavors will develope.
CAN devellop. Not will.
Good winemaking practice means that you press and then transfer juice to a secondary.
Then let it end fermenting and wiat a few weeks.
Next rack of the sediment and wait a few months.
Then rack again from the fine dust that has formed, and wait again a few months.
Lees might be attacked by bacteria or yeast and can devellop a bad taste and smell.
There are different views on this.
There are grape winemakers that will let the fermentation be done all the way on the pulp. And when done even let the wine sit longer on the pulp. Even for some weeks. Extended maceraration this is called.
Then they press and transfer to secondary.
There are grape winemakers that let their wine sit on the fine lees form many months. Stirring regularly. Sur-Lie gaingb this is called and will give the wine a feeling of sweetness (while it is not) and give the wine more mouthfeel.
Both methods are used in grape winemaking.
They should be used when you exactly know what you are doing.
If your new to winemaking rack every few months and then bottle.
When your experienced try experimenting and see what works for you.
Luc