There is always tension between buying new things that exist now or using that money to build something new for the future and making do with what you have in the near term.
Which choice should your service pick? (Navy)
Should we buy more things that exist now, or make do with what we have and put more money in research to buy a better thing in the future?
https://www.csis.org/analysis/linking-national-security-and-innovation-part-1