An inordinate desire for economic development is considered to be like straws and grains of sand within the heart. If one is overly engaged in material activity, the heart will always remain disturbed. As stated by Narottama dasa Thakura:

samsara visanale, diva-nisi hiya jvale,
judaite na kainu upaya

In other words, endeavor for material opulence is against the principle of devotional service.

From Srila Prabhupada’s purport to Cc Madhya 12.135