To me Tiger has some similarities to Skybus, which represent challenges Ryanair (Tiger's model) did not face.
Both are ULLC entering a market where there are existing and established LCC competitors who by comparsion offer a superior product generally at prices customers consider acceptable/affordable. Combine this with the ability for the existing players to take advantage of their economies of scale (share fixed costs over more planes, more options for recovering from MX problems etc), better route network and frequency, and to sell elsewise empty seats at low prices and life will be very hard for the ULCC.
In my mind neither Tiger OZ nor Skybus understood that their market already had expectations as to what a LCC should offer and that this expectation is at a level above what they deliver(ed).
While Ryanairs CEO often talks about how important it is for them to be ULLC, he doésn't talk about how important timing and location was to their success. Ryanair took off by being one of the first to take advantage of changes in regulation at a time when the competition was high cost - high fare, and the potential market for leisure/visiting family travel on the early routes (eg UK - Ireland) offered high growth with relatively moderate flight lengths (ie shorter than Aust routes) which kept costs low. In short they were not competiting on a route by route basis with a LCC (and initially they avoided head on competition with charters) and got the first mover advantage.