english: The first is that this product works well because we were effectively able to combine rigorous engineering science and analysis with user-centered design focused on the social and usage and economic factors important to wheelchair users in the developing countries.
non_english: Het eerste is dat dit product goed werkt omdat we strenge ingenieurskunst en analyse effectief konden combineren met op de gebruiker gericht design en rekening hielden  met sociale, traditionele en economische factoren voor rolstoelgebruikers in ontwikkelingslanden.