Why isn't China's military more transparent?

One of the common complaints against China's military modernization is that it lacks openness and transparency, according to an article carried by the Diplomat.

The article noted some possible reasons for China's unwillingness to increase military transparency.

First, China fears that foreign nations would use this transparency to weaken its defenses.

Second, China has a military doctrine that relies on the element of surprise to be effective.

Third, China's military capabilities are not as great as they generally perceived and greater transparency would allow opposing militaries to gain a greater understanding of what Chinese troops and hardware are capable of.