When Mathematics is No Longer Relevant
Here is the joke:
A: Andy had Rp.50,000 and he spent Rp.30,000 for a meal today. How much money does Andy have now?
B: Rp.20,000
A: That's incorrect. Andy has Rp.23,000 because he got 10% cashback from Gojek
B: ...
That joke is relevant to the battle between the two biggest online transportation providers in Indonesia: Gojek and Grab. Gojek, an Indonesian company, and Grab, a Malaysian but Singapore-based company, fight for dominance in Indonesia, at least, for the last two years.
In the last two years, there was a dramatic increase in the volume of electronic money in Indonesia. Started only from 683 million processed transactions valued Rp.7,1 trillion in 2016 and 943 million transactions valued Rp12,4 trillion in 2017. In 2018, there were 2.9 billion transactions valued Rp.47,2 trillion while in 2019, there was 2.7 million processed transactions with value Rp.69 trillion.

The Volume of Electronic Money Transactions in Indonesia. Note: * data until July 2019.
Source: Bank Indonesia, collected from Tempo
Source: Bank Indonesia, collected from Tempo
The market dominance in Indonesia can be one major step to dominance in the larger region. As the largest country in South East Asia, in terms of economy and population, Indonesia comprises 35% of the regional GDP of ASEAN (Association of South East Asian Nations) and 40% of the ASEAN population.
Indonesia also has a high variety of geographical features, ethnicity, and diversity resulting in any successful experience in adjusting new products with local demand give benefit for companies for further international expansion.
A price war is unavoidable to attract more customers and larger market share. This is obtained through cashback (or simply is a subsidy for customers) for every transaction, like the picture below.

Cashback from OVO and Gopay in merchant. Source: FinanceAsia
Gojek owns Gopay as its mobile wallet. While Grab makes cooperation with Indonesian e-wallet OVO. More providers actually compete in this price war, for example, LinkAja, DANA, Jenius, DOKU, PayTren, but only Gojek and Grab are the two largest players.
When to Stop
Stopping the price war is the best possible way to go to the next level: go public. Shares holders want to see the real growth of the companies, not just higher demand due to subsidy. Dividend and higher stock price are their main objectives. Thus, in the future, we can hardly see the price war anymore, and the 'correct' math is back.
(Thomas Soseco)