Bitcoin still has shortcomings such as lack of credit guarantee, poor security performance, and easy to cause deflation. At the same time, it has to face the competition of various emerging altcoins, and there is a greater
risk of substitution! Although I think this possibility is very small.
When you talk about poor security performance, what exactly do you mean? Personally I think bitcoin is secure, and it is more secure than most of the cryptocurrencies you’re going to see (altcoins). And I have not had any issues while making use of bitcoin, nothing like wallet being hacked etc.
For your account to be hacked it’s likely going to be due to an act of carelessness or a mistake that resulted to leaking information that has to do with your private keys. So, that’s why you as a crypto user has to be careful when you’re making use of it, you have to make sure that you’re not giving out any information that will give people access to you.