“Maximum number of retries” parameter in Delivery Properties
The default number of retries set for a delivery is 5. This means, in case of any undelivered message, the delivery will attempt to contact the address 5 times, the first day over the period of 24 hours. Second day onwards, the delivery will retry once to all the undelivered messages.
In case the value set in maximum number of retries is more than 5, there can be consequences resulting in slow performance in email execution.
Slow Processing of deliveries
A delivery going into retry mode will always end up piling up records for mtachild to process.
Though the Retry option ensures that the mail is delivered to temporarily unavailable recipients, increasing the number of retries can hamper the entire processing speed of mtachild.
This may not only affect a single delivery but can also impact the processing of other deliveries since mtachild processes each delivery.
Hence, it is always adviced to keep the value set to a maximum value of 5 and not more than that. This can be lowered as well.