Drive failures are random.
Some drives die ten minutes after you plug them in. Some go on for five, ten years. There's a whole lot in between. It depends on manufacturing design and batches, temperatures, usage patterns, even where you live will affect it.
There's no easy way to predict drive failures. And even if you manage to predict some types of failure, other types can happen without any warning whatsoever.
If you care about your data at all, you need backups. That pretty much means storing another copy - the chances of two drives failing simultaneously is considerably lower than a single one. If you want to be safer, you can have an offline backup - keep the backup drive unplugged, so it's not wearing down at a similar rate to the primary drive. If you really care about your data, consider having an offsite backup - that's a backup stored elsewhere, e.g. at a friend's home, in case of fire or other disaster.
That said, research indicates that failure is significantly more likely both in the first three months and after the first two years. That does not mean it can't fail in between; it's just slightly lower probability.