Here's the scenario:
Customer fills out form.
Makes a certain choice from the dropdown.
That choice sets off a series of emails.
Before that email flow is finished, same customer fills out the same form, but makes a different choice from the dropdown.
That new choice sets off a separate series of emails.
Does that then stop the first series of emails?
In my current case I have 5 products.
But that could easily increase over time.
The client does not like the individual checkboxes, and prefers the dropdown.
But I might be able to persuade if there's a solid functional reason.
Even if you use a (single-select) dropdown, you can still use it to manage a single semi-colon delimited field. You would use the Forms JS API for this, and I definitely would prefer that to managing concatenated fields on the back end.
But more to the point, this is still overengineering even if you let the field have only one value at a time. If a Data Value Changes trigger brings someone into a flow, they don't get booted from the flow if the value changes again later. They're already in the flow. And you can (and probably should) be using list or program membership to permanently record their interest anyway.
Compiling lists based interest sounds good.
One question:
If I make a list for people who choose product A, all those people get put there.
If one of them then chooses product B, they get put in the list I make for product B.
Do they get removed from the list for Product A?
If I make a list for people who choose product A, all those people get put there.
If one of them then chooses product B, they get put in the list I make for product B.
Do they get removed from the list for Product A?
Of course not! I think you have a preconception that Marketo has these mutual exclusivity rules. While that's true in certain cases (like a single text field) Marketo is by and large a one-to-many system.
But doesn't the second choice overwrite the first in the contact record?
Only if you're (a) using a single field for product interest (certainly not recommended) and (b) you re-check the value of that field after the lead has entered the flow.
But even then, it won't disrupt the email drips?
I'm using a dropdown.
Should I use separate check boxes instead?