There was nothing wrong with RMS Titanic. Her first sister, RMS Olympic, trundled along until being scapped in 1936 after the merger with Cunard. The issue with the Titanic was that she was driven into an iceberg.

EDIT: To understand the story of RMS Titanic, there are many superb books you could read (David Brown's 'Last Log of the Titanic' is a favourite of mine) but I'd recommend reading this, which is IMO the absolute best: https://thehistorypress.co.uk/publication/report-into-the-loss-of-the-ss-titanic

EDIT 2: I've been a Titanorak for decades and used to post regularly on Reddit but I'm past all that now. I'm not an expert. If you want to read the opinions of experts, visit Encyclopedia Titanica and peruse the articles there. Avoid books pushing conspiracy theories (coal fire damage, swapped ships, etc.) and go to the original source material: the British and American Enquiries, both of which are available online. You'll have a blast and enjoy the rabbit holes, and perhaps even make new friends; I did!