Nadex Binary bid/ask spread question

Hi,

During the day, Nadex binaries such as the GBP/JPY have a bid/ask spread of perhaps 6 dollars.

At night, that bid/ask spread goes up to as much as 14 dollars.

So a 4 hour contract that was 69/75 during the day goes to 65/83 at night.

Does trading the nightly contracts with this larger bid/ask spread decrease your chances of winning as opposed to trading in daytime?

Or does the slower markets and lower liquidity (hence the larger bid/ask spread) make everything balance out?

I am very curious about this.

Thank you for your help.