Is the train from Guangzhou South to Shenzhen North often late?

Generally, there are two kinds of high-speed trains from Guangzhou south to Shenzhen north, one is from Guangzhou south and the other is from Shenzhen north, which will not be delayed. The other one is from other places, passing through Guangzhou South and ending in Shenzhen North. For example, the train starts from Changsha and ends in Shenzhen North. You get on the bus at Guangzhou South halfway. In case of bad weather or other factors, it is possible to arrive at Guangzhou South late, but this situation is rare.