I believe that planning succeeds better than just ESP. If you need parts, you always need to have at least two suppliers for each part and hopefully three or more. Why? Just for the reasons you stated. In a crunch, you need options. If you have a sorted list of suppliers, you can quickly find a replacement source for a while if your primary source experiences unexpected difficulties.
It is all about good risk management and planning.
Just my opinion.
As we unveil EE Times’ 2015 Silicon 60 list, journalist & Silicon 60 researcher Peter Clarke hosts a conversation on startups in the electronics industry. Panelists Dan Armbrust (investment firm Silicon Catalyst), Andrew Kau (venture capital firm Walden International), and Stan Boland (successful serial entrepreneur, former CEO of Neul, Icera) join in the live debate.