This is because your hardware wallet keeps your private keys safe offline from online risk and threats like hackers, but Trust wallet is more secured mobile crypto wallet .
It is still necessary to follow the wallet security to ensure proper fund security, therefore you have to write down your recovery phrase and attach your passcode to your wallet .

Trust wallet is the best alternative because it gives comprehensive support for different Blockchain and crypto asset .
 
The reason why hardware wallet is better than i mobile phone is that phones will often be stolen, hacked it can be in possession of anyone at any time.
An offline Trezor or Ledger cannot be hacked,it can only be stolen physically .

Offline wallets that is stored in a safe can't be accessed via the internet or WiFi, and that is the only way to hack mobile wallets.

The only fool-proof way of storing password keys is in the brain, which can only be hacked through drugs and hypnosis.
 Memory is capable of making mistakes . Time, sickness, ageing,trauma and disease can erase even the best kept memories.