Why isn't there a Buddhist Bible? Why is it that Buddhism never compiled a reasonably concise set of canonical texts like the Bible? Buddhism itself has universal beliefs such as the 4 Noble Truths, the Eightfold Path and the notion of going for refuge. To me then it doesn't seem unreasonable that there could have been a Buddhist Bible that complied these central beliefs in the same way as the Christian Bible. 

Even though the Christian world is diverse they still manage with one Bible (though I do appreciate there are different version such as the Orthodox Bible) and this Bible forms the basis of new forms of Christianity or new emphasis on Christian belief. However Buddhism seems to have an enormous array of texts over a number of different canons (Pali, Chinese, Tibetan) and commentaries and para canonical texts. Why the difference?

Is there something in the history or culture of these two religions that caused them to treat their texts differently. Am I wrong and the differences aren't really there if you look at it correctly? Is it a theological matter? I appreciate you could ask the same question about Islam and Hinduism (I think) but I want to keep the question as on-topic and tractable as possible.
Why is it that Buddhism never compiled a reasonably concise set of canonical texts like the Bible?

One could equally ask, "why didn't Christianity compile a lengthy and diverse set of canonical texts like the Tripiṭaka?"

The thing is, Buddhism does have a canonical set of texts that are widely viewed by all major Buddhist traditions as canonical (as far as being the teachings given by the Buddha during his life time), organized into books and sections somewhat like the Christian bible. And while the exact makeup of the set differs from tradition to tradition, the core texts (mainly the first four nikayas of the sutta pitaka in Pali - the agamas in Chinese), are agreed upon as canonical. This is not dissimilar to the situation that exists between Judaism and Christianity. 

So, there only remains the question, why is the Buddhist canon not "reasonably concise"?

The first reason for the difference in length is a great amount of repetition, brought about both by 1) the fact that Buddhism was orally transmitted for so long and repetition helped with memorization, and 2) the state of having a good number of the same teachings given multiple times in slightly different contexts and faithfully recorded in duplicate, triplicate, etc.

The second reason is the discrepancy in time span. Jesus taught for around three years before getting himself killed; the Buddha lived to the ripe old age of 80, teaching for 45 years from the time of his enlightenment. One scholar (Rhys-Davids, IIRC) estimated that, all repetition removed, the Tipitaka is approximately eleven times the size of the Christian bible. Given that the Buddha taught fifteen times as long as Jesus, this seems like a fairly reasonable difference.

EDIT: removed the third reason.