You don't have to, chart are based on their own analysis, of course you can make your own and just disregard the chart if you don't agree with the TA.
The market is full of speculators and experts, but that does not mean they are right all the time and we should follow them, there's nothing we can rely but ourselves and we should trust out own.
Exactly what the OP needs to understand, there is no need getting into arguments with someone about his or her own strategies, as long as its working for that person and you're not compelled to follow suit then it's fine.
That's not to say trading strategy works all the time or is reliable, but if you have tried out a particular one, and you believe it works for you, then keep using it, it will help build your confidence in trading.