Many people confuse the meaning wattage ratings - they have little to do with volume or clarity - and marketing info does not make anything clearer for those who don't know the difference. No offense intended to anyone, but you need to know a few things about stereo equipment to make good buying choices, or ask someone who does, not a salesman who just wants to make a sale.
Wattage is the clean power output rating of an amp, and a power input rating of a speaker. It's the capability limit of a device, not volume. Going beyond the capability rating of either amp or speaker will produce poor sound.
Just because a speaker is rated to handle 100w does not mean you can run a lower powered head unit or amp to full output and expect clean sound. Head units supply minimal power to speakers, they are intended to produce enough output for loud conversation levels, no more. If you want party level volume, you need a lot more power.
Wattage ratings exist so you can match speakers and amps together for the best output. But even the best amp in the world can and will be overdriven into clipping if you crank it too high. The general rule of thumb is to match wattage ratings or go a bit higher on the amp by up to 20% for headroom. A lot of people will buy nice speakers, and then run them with a crappy amp and wonder why it sounds like shit. You need quality amps to drive speakers properly, and you need quality speakers to make good sound, or you're just wasting time and money if you only do half.
I've been an audiophile since getting my first decent stereo system when I was 18, and I see rookie mistakes with amps, receivers, speakers, subs, and wire all the time. No sense spending $1000 on speakers and buying a $50 amp or head unit to drive them. Same goes for $1000 amp with $50 worth of speakers. Neither will sound its best.
And speaker wire is wire - there's nothing magical about over-priced wire - Monster brand is the biggest scam out there. Any decent 16-14awg copper wire will sound the same, period, ohm's law and electrical theory applies equally to all types of wire. The only exception for boating is possible corrosion issues with copper. Marine wire is tinned to resist corrosion.
I usually just tell people to follow the ratings and match them exactly to keep it simple and you'll have a decent sounding system. But no matter how much you spend, even $20,000 worth of gear, you can still crank it too high and get shitty sound.