Auto increment not starting from 1

Question

Hello I will be glad if anyone can help me. I created a custom number field on the Lead Object. Sales_Ready_Counter__c

I wrote a trigger to increment Sales_Ready_Counter__c by 1 whenever a custom picklist (Sales_Ready__c) value changes as follows:

If Sales_Ready__c == 'yes' then increment Sales_Ready_Counter__c by 1
Sales_Ready_Counter__c starts from Zero (0). I want it to start from 1 instead of starting from 0. I can't figure out what I am doing wrong, please help review, my code is below:

trigger updateLeadSalesReadyCounter on Lead (before insert, before update) {
    for(Lead l :Trigger.new)
try 
{
    Lead oldSR = Trigger.oldMap.get(l.Id);
    Boolean oldStatus = oldSR.Sales_Ready__c.equals('Yes');
    Boolean newStatus = l.Sales_Ready__c.equals('Yes');

        if (!oldStatus && newStatus)
            {
                if(l.Sales_Ready__c != Null)
                {
                    if(l.Sales_Ready__c == 'Yes')
                        {
                            l.Sales_Ready_Counter__c = l.Sales_Ready_Counter__c != Null ? l.Sales_Ready_Counter__c +1: 0;
                        }   
                }   
            }   
    }   
    catch(System.NullPointerException e)
        {
            //
        }       
}

Answer 1

If you give your line as

l.Sales_Ready_Counter__c = l.Sales_Ready_Counter__c != Null ? l.Sales_Ready_Counter__c +1: 1;

Then for the first time when the field is null, the value will be set to 1. In every other situation the value in there will be incremented by 1. Hope my understanding is correct. Thanks