Bankroll Irregularities in skeme's FAQ

[Hosayif]

Recently, some one asked about faqs for this forum and i stumbled upon skeme's faq.

Q: What is a proper bankroll for each limit?

A: General consensus is that a player should keep at least 20 buyins for each limit he's playing. Excluding poor beginner play, bad bankroll management is the biggest reason that new players go bust. Do yourself a favor and only play in games you can afford.

Limit: $0.01/$0.02 | Needed: $100
Limit: $0.05/$0.10 | Needed: $200
Limit: $0.10/$0.25 | Needed: $500
Limit: $0.25/$0.50 | Needed: $1000
Limit: $0.50/$1.00 | Needed: $2000
Limit: $1.00/$2.00 | Needed: $4000
Limit: $2.00/$4.00 | Needed: $8000

If for each limit, you have 20 buy-ins, why is the buy in for .01-.02 250 big blinds while the buyin at 2-4 is only 100 big blinds?