أنشئ حسابًا أو سجّل الدخول للانضمام إلى مجتمعك المهني.
Market analysis and screening for: competitors/potential competitors, Customers and their regular behaviours and habits.
Legalities and governmental issues.
Regardless how smart your idea is and what needs it fills, if it's not analysed correctly (targeting the right customers at right places) and you didn't know what do you competitors serve, how did similar startups failed, you will face many difficulties of all levels such: Designing, Developing, Marketing.
My point, pre-sales or pre-anything usually make you avoid so many troubles later, and the failing cost in early stages of any project is always less than failing while launching for example.
It is very basic concept in any new business whether is was software or product line.