Why is there a delay in order execution during the market opening?

The delay in order execution during market opening hours may arise due to one of two reasons:

Exchange Capacity: If the number of orders surpasses the maximum capacity the exchange can handle, it can lead to congestion in the exchange lines. Consequently, your order may take a few seconds to be processed.

Broker Order Queue: Brokers connect to exchanges through leased lines, each with a designated order-per-second capacity. If this capacity is exceeded, orders enter a queue, causing a delay of a few seconds in order processing.