Success as an end is contradictory to the enterprising process. Do entrepreneurs see success differently? Will be happy to get any leads to existing research reference.
Maybe not an oxymoron, but for sure the concept of "success" in entrepreneurship studies strongly depends on entrepreneur's motivation and satisfaction threeshold. We can look for "objective" measure of success, but I think we risk missing interesting phenomena (just think to social entrepreneurship f.i.).
Here is a reference that could represent an interesting starting point on this issue:
DeTienne D.R., Shepherd D.A., De Castro J.O. (2008) The fallacy of “only the strong survive”: The effects of extrinsic motivation on the persistence decisions for under-performing firms, Journal of Business Venturing, 23, pp. 528-546
I agree with Katerina. Every entrepreneurial effort added to the experience which which may yield high dividends from the one effort that he succeeds. Shane (2003) argues that success is not an essential factor for entrepreneurship and states that the continuity of entrepreneurial effort also as important as successful ones.
Entrepreneurial process always does not end up with success.
You might also have a look at works such as the following which I think do a pretty good job of questioning what we are doing when we use 'entrepreneur' even when those uses seem illogical:
Kenny, K. and S. Scriver (2012). "Dangerously empty? Hegemony and the construction of the Irish entrepreneur." Organization 19(5): 615-633.
Marttila, T. (2012). The Culture of Enterprise in Neoliberalism: Specters of Entrepreneurship. New York / London:, Routledge.