Yes, any time someone says "I'm going to make a thing more reliable by adding more things to it" I either want to buy them a copy of Normal Accidents or hit them over the head with mine.
How bad are the effects of an interruption for you? Google has servers running every day, but you with one server can afford to gamble on it, since it probably won't fail for years - no matter the hardware though, keep a backup, because data loss is permanent. Would you lose millions of dollars a minute, or would you just have to send an email to customers saying "oops"?
Risk management is a normal part of business - every business does it. Typically the risk is not brought down all the way to zero, but to an acceptable level. The milk truck may crash and the grocery store will be out of milk that day - they don't send three trucks and use a quorum.
If you want to guarantee above-normal uptime, feel free, but it costs you. Google has servers failing every day just because they have so many, but you are not Google and you most likely won't experience a hardware failure for years. You should have a backup because data loss is permanent, but you might not need redundancy for your online systems. Depending on what your business does.
