BNB Chain details causes of blockchain transaction congestion

Blockchain transaction congestion arises when the number of transactions attempting to use a network outpaces its capacity to process them efficiently. This leads to growing backlogs, increased transaction fees, or uneven delays depending on the network and type of activity requesting blockspace. Blockchains batch transactions into discrete blocks, each with its own limit for data or computational work. When more activity takes place than a block can accommodate, transactions are left pending, awaiting inclusion as new blocks are produced.

Source: CoinTurk News