Pattern Day Trading:
The SEC defines a day trade as any trade that is opened and closed within the same trading day. They define pattern day trading as 4 or more day trades within 5 trading days. This means that even one trade per day would classify the trader as a pattern day trader, and the restrictions would then apply.
Preventing Day Trading:
If a trader is classified as a pattern day trader according to the SEC definition, and the trader does not have the required $25,000 deposit, their trading account will be frozen for 90 days. Once this happens, the trader will either have to deposit enough equity to bring their trading account up to the $25,000 limit, or wait until the 90 day hold has expired.
Other Markets:
Initially, the day trading restrictions appear to prevent day trading completely, but the restrictions only apply to US stock markets. The US futures and currency markets can be day traded without any restrictions or minimum deposits (except the exchange margin requirements), so there are still plenty of markets available for day trading, and many of these markets are better suited for day trading anyway.
Or avoid all this by moving to the UK lol.