Those that are waiting for a dip before starting are a joke of a Bitcoin investor because they might not even start their Bitcoin accumulation journey at all, because even when it dip, they will say that it may dip further so they will wait, and by doing so the price might start appreciating from there which will discourage them the more from buying, and that is procrastination setting in in disguise.
So it is never a good idea to be waiting for a dip before starting your Bitcoin investment, the best way to go about it in my own opinion is by buying anytime your discretionary income is available not minding the price, because in the nearest future, this current price will be like a steal, and it will be too cheap when we look back.
The truth is if a person mindset is long term bitcoin holding less say 4 to 10 years or more there is no need for the person to be waiting for bitcoin to dip before her or she can get started with bitcoin. As for those guys who are waiting for bitcoin to dip before they can get started with bitcoin they are very unserious guys, bitcoin is a store of value with potential returns, so why wait for bitcoin to dip before you can start accumulating bitcoin and hold? bitcoin can be accumulated at any fucking time and hold for long term, less say 4 to 10 years or longer, that's if your discretionary is made available, waiting for bitcoin to dip before starting your bitcoin investment is just another way to delay your investment journey, or your might even end up not getting started at, all the name of waiting for bitcoin to dip before you can start accumulating and and hold.
This is where Bitcoin knowledge comes to play, it takes an investor that understands that Bitcoin price will always increase and reach ATH in the future. Bitcoin is volatile and no need to wait for it to dip further before buying when you have available fund at hand. Unless you're excessively rich you can spend the fund that is intended for Bitcoin accumulation into a less important thing.
Some people can argue that it is better to buy during dip than when price is pumping, this is true but they need to consider that they can buy at present price then it'll start to rally and they'd be in profit. People who waits till it dip some more before buying will most likely panic and sell if it continues to dip further. If you want to succeed in long term investment you need to care less if price is dumped or is pumping, your goal will be to keep buying into the long term so far you have your discretionary funds at hand.