I chose 4 just because it's easier for me to manage.
If you have too many bets you may not have time to place them all.

For example on bet 9 I place 21 bets in total (3 on sixains and 18 on single numbers) covering 2 'even' chances. This is easy enough on an RNG wheel which is manageable at your own pace, but tricky when playing live.(which I prefer)

Bear in mind, I'm not just watching High/Low, Odd/Even & Red/Black I'm observing another 70 or so even chances.
We all know how dangerous just following one even chance (or for that matter just one system)  can be and I suspect we've all seen runs approaching 20 or even more!

Over 1000 spins betting on just 1 sleep could easily give over 1500 bets.
While waiting for 4 could only gives around 150 bets.

In my earlier example I had 10 bets in 17 spins.
It proved profitable after 10 bets but was just as profitable after just 1 bet!

By using the Replay button in RKG I'm able to determine other methods would have fared as below:
(The numbers after the system title  refer to the button numbers in RKG and chapter numbers in my book.)
The numbers played were 30,30,17,35,9,7,9,9,17,19,4,17,5,22,27,4,8,31,

Using other systems from RKG could have proved more profitable

• The Prudential System (chapter/button IV) showed a profit of 8 after 4 spins. But would have ,lost 5 over all 17 spins.
• The Ex-Croupiers system (X) would have shown a profit of 7.
• The Capitalist System (XI) would have shown a profit of 81 !!! (albeit at some risk)
• Mini Capitalists system would have shown a profit of 18
• 
  
  • The infallible system 37 after 8 spins.I may be wrong here but still a good profit!
  • The Paterson (XVI) would have shown a profit of 11 after 2 spins or 7 after 17
  All the above techniques are in RouletteKeyGold
  some (not all)  are explained on my website at http://www.winningrouletteplayer.com/systems.html
  but I'd rather you bought my book (isbn 9781500758806) or tried RKG for yourselves.
  
  
  
  
  

I chose a streak of 4 losses as if counting all the even chances this would give approximately 1 bet per spin sometimes more.

If I chose 3 there would be over 2 bets for every spin.
This would get far too complicated to manage.

Admittedly these figures are counting the results of 43 even chances (sets of 18 numbers) when most people only follow 6!

RouletteKeyGold keeps track of around 70 even chances so you could wait for every run of 6,7 or even 8 to keep the number of bets manageable.