Some are discovered (e.g. some entrepreneurs have started producing something especially for left-handed people; about 10% of people are left-handed, but lots of products are still more convenient for right-handed people), some are created (e.g. if you develop a completely new product and start selling it or if you manage to convince a completely new market segment to buy your product).

I agree with Tila Vissak. But I would qualify that not all opportunities lead to success. From my informal observations (I work with a lot of entrepreneurs), I would guess that found opportunities are more likely to lead to success than created ones. Even the created ones are generally more successful if the creators infuse them with "found" opportunities by recruiting potential customers to give feedback early in the development phase and changing the original idea to better match the "found" opportunities. This would be an interesting research question if no one has already addressed it.

Agree with Tiia. Opportunities are discovered as well as created, depending on the context, underlying (social) mechanisms and action patterns. We recently reviewed and synthesized the entrepreneurial opportunity literature, to craft an overview of the "evidence" on opportunity formation. See link below.

Article Creating the Future Together: Toward a Framework for Researc...

Well, I'm happy to see that Linton has cited the seminal work on Entrepreneurship domain, Shane & Venkataraman's typology of opportunity recognition as the heart of entrepreneurship. Also i agree with Tiia, Hull and Romme's answers as well.

Beside to think, either opportunities are created or discovered, this Barringer and Ireland's (2008) approach would add value. they defined, an opportunity is a favorable set of circumstances that creates the need for a new product, service, or business idea. Furthermore, they postulated that, opportunities are either externally stimulated or internally stimulated.

Internal stimulation: An entrepreneur decides to start a firm, searches for and recognizes an opportunity, then starts a business.

External stimulation: An entrepreneur recognizes a problem or an opportunity gap (external environment) and creates a business to fill it.

Given this internal and external stimulation, one can assume that, internal stimulation links to creation of opportunities. Because internal stimuli of an entrepreneur leads to create an opportunity, whereas external stimulation links to recognizing an opportunity. This is because, external environmental factors led entrepreneurs to recognize opportunities.

Barringer B. R. and Ireland R. D. (2008). Entrepreneurship: Successfully Launching New Ventures, 4th ed. Prentice Hall.

I'm not sure about the usefulness of a sharp distinction between opportunity created and discovered. Maybe we should conceptualize entrepreneurial opportunities as a nexus of entrepreneur's capabilities and external stimulus. Results of moving around to such nexus may sometimes look like a discover of something were there from the beginning, sometime like something that arise as a non foreseen outcomes. Since creation and discovery are linked each other intimately we may try to think about entrepreneurial opportunities in a different way.

"opportunities are waiting to be discovered" is the approach of American researchers (Shane and Venkataraman, 2000). It implies that one can deliberately search for an opportunity. However, Austrian researchers (i.e., Kirzner, 1978) view opportunity discovery is by chance (fortuitous discovery). Most important discoveries are made by chance (i.e., Steam engine (George Stevenson); Penciling (Alexander Fleming). When ever somebody is interested in solving a problem, he finds a solution by chance. Deliberate searching for opportunity would bring about results but not as effective as the one found by chance. Most of the successful entrepreneurs fall into the Austrian view .

I am now focusing my research on entrepreneurial passion and opportunity. To distinguish whether opportunity is created or discovered is quite interesting because if we relate signature strength/ domain-relevant construct with opportunity, then we could see clearly which one is more relevant. If we look at creator like Edison or Tesla, they were motivate by finding solution for something ground-breaking. On the other hand, if we look at innovator like Jobs or Akio Morita (Sony), they were motivate by finding improvement with existing solution. Thus both involved creation and discovery..it is just like chicken and egg analogy.

Based on Venkataraman, Dew & Forster (2012), rather than distinguish creation or discovery, perhaps they suggested we see opportunities as epistemological constructs in irreducible tripod's perspective of objective, subjective and inter subjective.In short, based on the explanation, opportunities hence in fact are artefacts.

http://10.5465/amr.2011.0079 ACAD MANAGE REV January 1, 2012 vol. 37 no. 1 21-33

Opportunity can both be discovered and created, discovering an opportunity has to do with filling up a gap that others could not recognise as important, creating an opportunity is an imaginative/creative work of the entrepreneur by coming up with a new product.

This might help you  http://the-mighty-entrepreneur.blogspot.com.es/2010/03/opportunities-are-they-created-or.html

opportunities can be socially constructed also.

they can be also enacted.

Gabriel, the discovery and/or creation of entrepreneurial opportunity is also highly dependent on a range of other factors, not least the extent to which the individual has developed and nurtured entrepreneurial capacity and know-how. Other factors such as the amenability of the environment, the availability of the requisite human and non-human resources (including finance and credit) and the socio-cultural readiness of people (including clients) that the entrepreneur will be doing 'must have' and not simply 'nice to have' business with. Interesting.

I recommend reading Ramoglou, S., and Tsang, E.W.K (2016) "A realist perspective of entrepreneurship: Opportunities as propensities", Academy of Management Review, Vol. 41, No. 3, p. 410-434.

The authors explicitly discuss the shortcomings of the "discovery approach" and "creation approach", resulting in an alternative view of opportunities.