While the specific article "Revolut and Monzo should heed Atom Bank’s not-so-tiny challenges" could not be directly accessed, information from related Financial Times articles indicates Atom Bank's financial struggles despite growth. One article from July 2018 states that Atom Bank's pricing promotions led to increased losses, even as its assets more than tripled to £2 billion in the last financial year. This suggests that aggressive strategies to attract customers may come at the cost of profitability.

Another report from July 2019 noted that Atom Bank was starting to make money on loans, with Chief Mark Mullen stating the group defied closure and held its nerve during a mortgage price war. However, earlier in September 2016, Atom Bank had attracted significant early interest from mobile customers, signing up 40,000 potential customers, but only 2,000 of them had opened accounts. This highlights a persistent challenge for digital banks: converting initial interest into active, revenue-generating customer relationships.

The broader context of fintechs like Revolut, Monzo, and Starling, as discussed in a separate FT article from July 2021, reveals that the pandemic forced these banks to cut costs and seek new income streams to survive. While some, like Revolut, claimed monthly profitability at times due to factors like a boom in cryptocurrency trading, and Monzo saw revenue increase, they all face the ongoing quest for sustainable long-term profitability. The financial experiences of Atom Bank, with its losses despite asset growth and conversion challenges, serve as a cautionary tale for other digital banks in their pursuit of market share and profitability.