Why Do Market Makers Prefer to Trade Weekly Options near Expiration?

Market makers prefer to trade weekly options near expiration because they are typically Delta-neutral, high-Gamma traders. High Gamma means they can quickly re-hedge their Delta for small price movements, capturing the bid-ask spread profits more frequently.

The rapid Theta decay also allows them to profit from the time decay of options they are short, as long as they can manage the associated Gamma risk.