What is the best platform for altcoin?

Could you please elaborate on what factors one should consider when determining the best platform for trading altcoins? Is it crucial to look for a platform with a wide range of altcoins available for trading, or is the security and reputation of the platform more important? Additionally, how do transaction fees and trading volumes play a role in the selection process? Is there a specific platform that stands out as the best choice for altcoin trading, or does it vary depending on individual needs and preferences?