Anytime is better for investment if it is a long term investment. For short term investment, more scrupulous study is required. Thus if long term investment is in mind then dont look at current price, soon or later great returns are waiting.
If we don't have time due to busy with daily activities so don't have to continue
monitoring the market prices, long-term investment is better than short term investment.
But if we always have time, then short term investment (trading) is better than investing.