Drive quality is enormously better than it used to be. The manufacturers wouldn't be offering five year warranties if it wasn't. But, as bledd says, this is no excuse for not backing up your data.
My 'career' in IT has been long enough that I remember the first HDDs for PCs. There was one particular 10MB (Rodime IIRC and I do mean MB) 5.25" full-height drive that, when one failed on site, we used to order two or three from stores so there was a chance we'd get one that wasn't DOA. I also remember a batch of 40MB 5.25" half-height Micropolis drives that failed straight from the box. How often do we get DOA drives these days?