A collision in the ethernet usually occurs during the transmission of the first 64 bytes (512 bits) in the frame.
If a collision occurs during this 512-bit time transmission, the collision becomes a delayed collision which invites an increment in CDCR.
There may be some causes for a delayed collision. One of them can be a mismatch of the full-duplex settings between the edges of the link on the improper network configuration that does not comply with the specification. An excessive signal crosstalk between the twisted pair lines, and a damaged hardware may also cause a delayed collision.