https://www.monero.how/why-monero-vs-bitcoin

Why might #Monero see greater future adoption than Bitcoin?
The most critical flaw in Bitcoin is its lack of privacy. If you give me your Bitcoin wallet address so that I can send you a payment, you immediately compromise your privacy. I can see as a matter of public record how much money you have in your Bitcoin wallet (there are messy workarounds to attempt to fix this problem, which we will address shortly). The same situation applies even if you are the one sending Bitcoin. Any recipient can then see how much money you have in your Bitcoin wallet, both now and in perpetuity. To understand how critical this privacy problem is, consider the following scenarios:

1. You are travelling through parts of a country with a medium to high violent crime rate. You need to use some of your Bitcoin to pay for something. If every person you transact with knows exactly how much money you have, this is a threat to your personal physical safety.

2. You are a business that receives a payment from a supplier. That supplier will be able to see how much money your business has, and therefore can guess at how price sensitive you are in future negotiations. They can see every single other payment you’ve ever received to that Bitcoin address, and therefore determine what other suppliers you are dealing with and how much you are paying those suppliers. They may be able to roughly determine how many customers you have and how much you charge your customers. This is commercially sensitive information that damages your negotiating position enough to cause you relative financial loss.

3. You are a private citizen paying for online goods and services. You are aware that it is common practice for companies to attempt to use ‘price discrimination’ algorithms to attempt to determine the highest prices they can offer future services to you at, and you would prefer they do not have the information advantage of knowing how much you spend and where you spend it.

4. You sell cupcakes and receive Bitcoin as payment. It turns out that someone who owned that Bitcoin before you was involved in criminal activity. Now you are worried that you have become a suspect in a criminal case, because the movement of funds to you is a matter of public record. You are also worried that certain Bitcoins that you thought you owned will be considered ‘tainted’ and that others will refuse to accept them as payment.

Monero solves these privacy issues by automatically applying privacy techniques to every single transaction made. You can have confidence that it is not possible to own ‘tainted’ Monero. This is a concept in economics known as ‘fungibility’ and is historically considered an important characteristic for any currency to have.

The Bitcoin community has attempted to solve these problems by introducing ‘mixing’ features. Their solutions have been described as ‘a band aid over a stab wound’.