Complex sentence: This predicament ultimately left O'Leary devastated and desperate for extra rounds of funding to support the fledging business and ultimately taught him the critical lesson of always having more than one source of financing available when starting a new business.
Split into simpler sentences: This predicament ultimately left O'Leary devastated, and desperate for extra rounds of funding to support the fledging business. Because of this, he learned the critical lesson of always having more than one source of financing available when starting a new business.