I'm not talking about just the mobile market. That seems to be a common reaction. Traditional success ratios for PC publishers was 1 in 5 going back to the 90s. There's evidence this ratio has gone up as supply increases and demand has not grown accordingly. Some individual studios are more successful than this, but they are A) outliers and B) tend to fall back to the mean over the long term (say 10 years). Successful indie studios with 3 or more game (of which we are one) are extraordinarily rare.
In the end, this is a model. If you have better numbers from better sources that fit your personal situation, you should use those. The logic stands.