Volatility of bitcoin price is a serious business challenge. Even though bitcoin shows good promise, but in cash rich business like general stores and fast moving consumer goods business, the volatility throws a significant profitability challenge. Unless we find a solution to immediately settle the funds received in bitcoin, it will remain as a major roadblock for bitcoin to be accepted as a normal currency. Let me explain why,

Day 1:
Bitcoin price: $10,000
Product "A" cost: $100 or 0.01 btc
Seller sold 2 units of "A" and received 0.02 btc.

Day 2:
Bitcoin price: $12,000
Product "A" cost: $100 or 0.0084
Seller sold 5 units of "A" product and received 0.042

Day 3:
Bitcoin price: $14200
Product "A" cost: $100 or 0.0070
Seller sold 3 units of "A" product and received 0.021

So on day 3, the seller should hold (0.02+0.042+0.021) = 0.083 bitcoin for selling 10 units of "A" product whose dollar value in fiat is $1,000. TIll day 3, bitcoin price was increasing and the seller was receiving less amounts of bitcoins for the same value in dollar. Imagine, the bitcoin price crashed on day 4 and came down to $9,500. Lets calculate again,

Day 4:
Bitcoin price: $9,500
Bitcoin holding: 0.083
Dollar value: (0.083 X $9500) = $788.5

So on day 4, the seller is actually making a loss of $211.5 for the $1000 product. So unless that seller is really optimistic about bitcoin, he won't favor it to be used as a currency in his store. Either he would need a service which will help him to settle every bitcoin trade immediately using an intermediary or simple don't accept it.

Probably a big company can handle such losses, but a small trader will not be able to handle this where every penny counts. That's the business challenge I am referring to and it is a major roadblock for bitcoin to be accepted as a mainstream currency.