There are standard terminology in the market place. Market lingo should be followed to avoid misunderstanding, confusion or potentially wrong perception.

For example the most commonly used in everyday market are for trades done on the bid and offer.

Let's say the bid/offer is 1.05/1.06.

If someone sells to the 1.05 bid, this is called "hit the bid". The result is the bid being "hit" or "given". If someone buy from the 1.06 offer, this is called "take the offer". The result is the offer being "taken".

Now terms such as "sell down" and "buy up" to replace the above is not only misleading and confusing but can give a very wrong impression.

"Sell down" is synonymous to a sort of panic where sellers rush to get out at the avaialble bids while "Buy up" is synonymous to a moping up operation where a buying party is taking all the offers that come into the market.

Softwares or features that use these terms wrongly are signs that the programmers lack the experience in the area that their softwares are intended. This is why user experience is important. If you are a doctor and you can program, you can write a medical software in your field far better than one written by programmers in software companies who don't know about a doctor's work.

Therefore... if you are a contractor... if you are a teacher... if you are an accountant... if you are a secretary... if you are the one who shops for the groceries... if you are... you have the user experience that you can use to produce efficient softwares for people in your field. You speak their lingo and know what you want therefore you know what they want. You know what you mean therefore you know what they mean.

Keeping to accepted market terminology is so important.