Culture is a concept that is difficult to define and to communicate clearly, no matter how many caveats, codicils, inclusions and exclusions we can cram into a sentence! As a result, symbols which represent and communicate complex concepts are surely to be developed and used by individuals who have strong agreement that they have the same comprehensions. Then, the symbol and it's relationship what it represents is incorporated into the individual and group matrix of belief, value, cultural, and normative mental structures.
The Star, the Cross, and the Crescent are universal symbols for mythical, historical, and religious cultures that can take several lifetimes to study and argue about. They each make a statement that represents a religion that may be at the source of wars, community discord, or personal resentment. They can each also make a statement that evokes reverence, respect, or instant recognition of an implied agreement about complex religious values, beliefs or norms.
The complexities of culture are such that, once various agreements in meaning are reached, a symbol, rather than a repetitive set of detailed descriptions and definitions, becomes a more effective expression. Over time, the symbol, as a visual summary of the cultural meaning becomes a meaning in itself.
The problems with cultural symbols lies in the symbol remaining the same, while the complexity of meaning, belief, ideal, value or norm increases. When individuals develop their own structure of meaning, the symbol can no longer be a true representation of meaning to them. When there is an increase and a polarization of those formerly agreed, but who now disagree, the symbol can become a fractured symbol that has various meanings.
Also, when there is a change in the relationship between the symbol and what it represents, the symbol no longer serves as a coherent summary of meaning. When a company logo is replaced by a new logo, the older logo is not severed in it's relationship with the company, but it represents the historical relationship between the individual and the company or it's product. The new logo represents what the company or product are about in the present.
When the symbol is associated with a cultural entity that is no longer popular or no longer exists, the relationship between the symbol and what it represents can be severed, making it a meaningless symbol over time, or as people forget what is was that the symbol was connected to in the first place.
Whether disagreement develops as to what the symbol represents, the symbol becomes severed from what it represents, or the symbol is replaced with a new symbol, cultural symbols develop and become powerful referents when people develop very strong agreement between each other as to what the symbol is and what it represents. This results in rapid and essential communication of cultural values and norms.