Because

• it is not deterministic: A deterministic wallet is a system of deriving keys from a single starting point known as a seed. [1]
• require regular backups.
• viruses in the blockchain: Although these viruses do not infect your device but are incompatible with the antivirus software, which causes problems in the wallet
• difficult to use for beginners

All these things do not apply to who asked the question so I did not recommend it.