Don’t use Blockchain if you have following concerns

Privacy:

Every nodes in blockchain network can view all the transactions.Unlike the banking sector where you can view only your transactions.

Pseudonymity:

The pseudonym identifies a holder, that is, one or more human beings who possess but do not disclose their true names (that is, legal identities). Most pseudonym holders use pseudonyms because they wish to remain anonymous, but anonymity is difficult to achieve, and is often fraught with legal issues.In blockchain, the user can hide behind a wallet address.

Transaction costs:

For someone looking to send funds and get a quick confirmation, the appropriate fee to include depends on the cryptocurrency being sent and can vary greatly, depending on a number of factors, such as transaction size and network conditions.Each transaction has a cost,unlike a tweet on twitter or post on facebook or a story in Instagram.

Transaction speed:

Throughput:

Platform evolution:

Upgrades are easy in Centralized system,but very difficult in Peer-to-Peer. New patches or new changes are very difficult to circulate into 1000s of nodes in a blockchain network.

Blockchain size: