The Titanic was conceived as the White Star Line's response to intense competition from other mainly British and German shipping lines. The dramatic increase in the size of vessels brought economies of scale together with a significantly expanded capacity especially in terms of the number of available steerage passenger berths (mainly emigrants) from which the lines derived a significant proportion of their income. Increased speed and luxury appointments would lure business travellers, socialites and the affluent middle classes. The White Star Line responded to these challenges by moving it's main port of operation from Liverpool to Southampton and by commissioning Harland & Wolff to begin work on a trio of giant liners.
See: Conceiving a legend.