Brand loyalty to existing firms:

The existing brands have loyal customers, who keep purchasing products of the same brand although new entrants appear.

R&D requires heavy investments:

New entrants have to have a large amount of capital in order to invest in the important operations of research and development. This reduces the amount of potential entrants.

High economies of scale:

In order to success in the particular market field, the new entrant has to have sufficiently large scale of operations.

Time and cost of entry:

The competitors in the particular market field are so large that it requires a lot of time and money for potential in order to entry new markets.

Technological changes:

It is very difficult to build technology advanced products right from the start.

Riina - LG - Blu Ray Players