Franchises are good in the sense that consumers will shop at a recognizable brand first before they shop elsewhere. Also, franchises are able to get locations that non-franchise operations are not able to secure - as you know, location is extremely important in business. Franchises are also able to negotiate favourable prices, terms and source products or services that non-franchise operators can't.
One of the problems with franchisors is that they treat their franchisees as customers instead of business partners. The problem with this is that as a franchisee, you are bound to 'buy' from the franchisor and can't, like a regular customer out in the marketplace with many options, 'shop around' when you feel the franchisor is providing you with bad value.
Secondly, frachisors surcharge you for many things - both in the setup costs of the business - construction costs for the most part; and in the ongoing operation of the business - rent and many input costs. For example, many franchisors will become the primary leasee (one who leases or rents a premises) and then re-rent the premises or sub-lease the premises to the franchisee. What happens in many circumstances is that the franchisor will rent a unit for, say, $4,000, and then sub-lease it to the franchisee for $5500. This increases the cost for the franchisee, takes would-be profit out of the franchisee's pocket and increases the chances that the franchisee will not be profitable over the longrun, thereby losing the original investment the franchisee made.
In summary, if you are going to open a business, specialize in something over doing everything within a particular industry and also, from day one, have a plan to grow your business so you can compete with your competitors who also are trying to grow. If you don't grow, your competitors (and inflation) will make you uncompetitive over the long run.